CN1703919A - Method and apparatus for using switched multibeam antennas in a multiple access communication system - Google Patents

Abstract

In order to increase a capacity, or a number of mobile stations (MSs), or users, that may engage in concurrent communication sessions, a communication system (100) is provided that schedules a different MS, or user, (110-112) in each beam of multiple predetermined, fixed beams (160-165) associated with a coverage area, for example, a sector. By simultaneously scheduling a user in each beam of the multiple beams, a performance and throughput of communication system is significantly increased over the prior art. In one embodiment of the present invention, a portion of a shared communication channel that is allocated to each MS is concurrently transmitted to each MS via a beam associated with the MS. In other embodiments of the present invention, voice channels, data channels, and control channels associated with each MS scheduled in a beam may be concurrently transmitted to each MS via the beam associated with the MS.

Description

Method and apparatus for using switched multibeam antennas in a multiple access communication system

technical field

The present invention relates to wireless telecommunication systems, and more particularly to the use of switched multibeam antennas in wireless telecommunication systems.

Background technique

An important goal in designing a wireless communication system is to maximize system capacity, that is, to maximize the number of users that a communication system can serve simultaneously. One way to increase system capacity is to use smart antenna systems. A smart antenna system uses an array of antenna elements to wirelessly transmit information to a target mobile station (MS). The use of an array of smart components allows beamforming of the transmitted signal such that a narrower, more focused beam is transmitted to the MS. In other words, by adjusting the amplitude and phase of the signal transmitted to each antenna element, the desired beam can be formed. By beamforming the transmitted signals, multipath fading of the transmitted signals and interference to non-intended users is reduced because the beams are more narrowly focused.

There are two main types of smart antenna systems, switched beam antenna systems and adaptive antenna systems. In cellular communication systems, a switched beam antenna system involves the use of a plurality of predetermined, fixed beams in sectors of a cell. The outputs of multiple antenna assemblies of a switched beam antenna system are combined in such a way as to form narrow, directional beams that are spatially selective. The switched beam system switches the information intended for the MS from one beam to another as the target MS traverses the sector. In other words, when the MS is in the first beam of the plurality of beams, all transmit power available in the sector is allocated to the first beam. When the MS is in a second beam of the plurality of beams, all transmit power available in the sector is allocated to the second beam.

By limiting the signal transmitted to a particular MS to the beam containing that MS, system performance is improved because limiting the transmitted signal to the correct beam reduces the interference observed by other mobiles not in that beam. In addition, restricting the signal transmitted to a particular MS to the beam containing that MS allows the transmission power to be curtailed and with it the interference observed by other mobile stations. As a result, system capacity is improved because the reduction of interference allows increased frequency reuse in Time Division Multiple Access (TDMA) communication systems, or orthogonal code reuse in Code Division Multiple Access (CDMA) communication systems.

However, utilizing switched beam antenna systems to focus beam signals to target MSs traversing sectors is only beginning to address the problem of increasing system capacity, which is a continuing constraint on the operation of wireless communication systems. Therefore, there is a need for methods and apparatus for obtaining additional capacity improvements by utilizing switched beam antenna systems in wireless communication systems.

Description of drawings

Figure 1 is a block diagram of a communication system, in accordance with an embodiment of the present invention.

Figure 2 is a block diagram of a transmitting communication device, in accordance with an embodiment of the present invention.

3 is a block diagram of multiple transmit signal paths of a transmitting communication device, in accordance with an embodiment of the present invention.

4 is a block diagram of a sector of a communication system, in accordance with another embodiment of the present invention.

5 is a block diagram of a sector of a communication system, in accordance with another embodiment of the present invention.

6 is a block diagram of a sector of a communication system, in accordance with another embodiment of the present invention.

7 is a logic flow diagram of steps performed by a communication system in transmitting information to each of a plurality of mobile stations via a switched beam antenna system, in accordance with an embodiment of the present invention.

Detailed ways

To obtain additional capacity improvement by utilizing a switched beam antenna system in a wireless communication system, a communication system is provided in which each of a plurality of predetermined, fixed beams associated with a coverage area (particularly a sector) A beam schedules different MSs, or users. By simultaneously scheduling users in each of the plurality of beams, the performance and throughput of the communication system is significantly increased relative to the prior art. In one embodiment of the invention, a portion of the shared communication channel allocated to each MS is sent concurrently to each MS via a beam associated with the MS. In other embodiments of the invention, the voice channel, data channel, and control channel associated with each MS scheduled in a beam may be sent concurrently to each MS via the beam associated with the MS.

In general, embodiments of the invention include a method for communicating subscriber information to each of a plurality of mobile stations in a communication system comprising a plurality of mobile stations and a switched beam antenna system, wherein A switched beam antenna system includes an infrastructure and multiple beams for transmitting user information from the infrastructure to multiple mobile stations. The method includes scheduling different ones of the plurality of mobile stations to use each of the plurality of beams substantially simultaneously.

Another embodiment of the present invention includes a base station subsystem capable of operating in a communication system including a switched beam antenna system that generates a plurality of predetermined, fixed beams. The base station subsystem includes an antenna array including a plurality of array components, a plurality of weighters, wherein each of the plurality of weighters is connected to one of the plurality of components, and a processor connected to Each weighter of the plurality of weighters. The processor transmits a first set of weighting coefficients to the weighter for communicating information to a first mobile station of the plurality of mobile stations, and further transmits a second set of weighting coefficients to the weighter for communicating information to a plurality of mobile stations A second mobile station in the station, wherein the weighter utilizes a first set of weighting coefficients to transmit a first beam of the plurality of beams to the first mobile station, and wherein the weighter utilizes a second set of weighting coefficients to transmit to the second mobile station A second beam of the plurality of beams.

The present invention can be more fully described with reference to FIGS. 1-7. 1 is a block diagram of a wireless communication system 100, in accordance with an embodiment of the present invention. The communication system 100 includes a fixed wireless infrastructure including a base station subsystem (BSS) 102 . BSS 102 provides communication services to each of a plurality of mobile stations (MS) 110-112 located within a service coverage area (or cell) 150 served by the BSS. Cell 150 is divided into a number of geographic sectors 151-153 (three shown). The BSS 102 includes a plurality of Base Transceiver Stations (BTS) 104, 105 (two shown), each connected to an antenna 114 via a duplexer. Each BTS 104, 105 provides communication services via respective air interfaces 116-118 to MSs 110-112 located in sectors 151-153 in cell 150 served by the BTS. Each air interface 116-118 includes a plurality of communication channels including at least one packet data channel, a shared packet data channel, a pilot channel, a paging channel, and a synchronization channel.

Antenna 114 is a directional antenna that is divided into a plurality of antenna sectors 120, 130, 140 (three shown), where each sector of the plurality of antenna sectors corresponds to one of the plurality of geographic sectors 151-153. A geographic sector to which communications services are provided. Each antenna sector 120, 130, 140 includes an antenna array comprising a plurality of antenna elements (two are shown for each array). For example, antenna sector 120 includes antenna assemblies 121-122, antenna sector 130 includes antenna assemblies 131-132, and antenna sector 140 includes antenna assemblies 141-142. By utilizing an antenna array to transmit signals to MSs located within the sector served by the antenna array, the BSS 102 can transmit signals using beamforming techniques that switch beams. For example, as shown in FIG. 1, each sector 151-153 is associated with a plurality of fixed, predetermined beams 160-165, i.e., sector 151 is associated with beams 160 and 161, sector 152 is associated with beam 162 and 163, while sector 153 is associated with beams 164 and 165; however, those of ordinary skill in the art appreciate that the number of beams associated with each sector is arbitrary, depending on the designer's preference of the communications system 100. judgement. Each beam 160-165 is predetermined, fixed, rather than adaptively shaped, directional, and used by BSS 102 to send signals to MSs included in that beam.

The BSS 102 further includes a scheduler 106 and a base station controller (BSC) 108, which are respectively connected to each BTS 104, 105 in the BSS 102. In another embodiment of the invention, scheduler 106 may be included within BSC 108. The scheduler 106 determines an optimal beam of the plurality of beams 160-165 utilized by the BSS 102 (i.e., the BTS 104 of the BSS 102) to transmit signals to MSs served by the BTS.

Preferably, communication system 100 is a Code Division Multiple Access (CDMA) communication system that includes a plurality of orthogonal communication channels, although those of ordinary skill in the art appreciate that the present invention may be used in any wireless communication system, such as Time Division Multiple Access ( TDMA) communication system or Orthogonal Frequency Division Multiplexing (OFDM) communication system. Preferably, each communication channel of the plurality of communication channels includes one or more of a plurality of orthogonal spreading codes, such as Walsh codes. The use of spreading codes allows multiple communication channels to coexist in the same frequency band.

Figure 2 is a block diagram of a BTS 104, 105, in accordance with an embodiment of the present invention. Each BTS 104, 105 is connected to at least one antenna array 120, 130, 140 associated with the BSS 102, such as array 120, and includes a transmitter section 202 and a receiver section 204, which are respectively connected via a duplexer (not shown) to the array. Each of the transmitter portion 202 and the receiver portion 204 is further coupled to a processor 206, such as one or more microprocessors, microcontrollers, digital signal processors (DSPs), combinations thereof, or as known by those of ordinary skill in the art. other such devices are known. The processor 206 is further connected to, and/or includes, one or more associated storage devices 208, such as random access memory (RAM), dynamic random access memory (DRAM), and/or read only memory (ROM) or its equivalent, which stores data and programs executable by a processor. Processor 206 and associated storage device 208 allow BTS 104 to store information, perform calculations, and run software programs.

3 is a block diagram of multiple transmit signal paths 300, 301 for each BTS 104, 105, in accordance with an embodiment of the present invention. Each transmit signal path 300, 301 corresponds to one of a plurality of array elements (eg, array elements 121 and 122) of an antenna array (eg, antenna array 120) associated with the BTS. Data is provided to the BTS 104 by a data source 210 (eg, an interface to an external network such as the public switched telephone network (PSTN) or the Internet) or an application running on the processor 206 of the BTS.

Data source 210 is connected to processor 206 . As shown in FIG. 3 , the processor 206 includes an encoder 302 , a plurality of spreaders 306 , 308 , and a plurality of symbol mappers 310 , 312 . Encoder 302 receives data from data source 210 and encodes the data using a predetermined encoding scheme (eg, a block encoding scheme or a convolutional encoding scheme). The encoder 302 then transmits the encoded data to each of a plurality of spreaders 306,308. In another embodiment of the invention, the processor 206 may further include an interleaver that interleaves the encoded data before passing the encoded data to the plurality of spreaders 306,308.

Each of the plurality of spreaders 306, 308 is connected to a spreading code generator 304 and spreads the encoded data according to a spreading code, preferably a Walsh code, provided by the spreading code generator. The spreading codes generated by the spreading code generator 304 depend on the MSs to which the data is destined because the BSS 102 assigns a different spreading code to each MS located in the same sector among the multiple sectors 151-153 . Each spread 306, 308 then transmits the spread data to a respective one of a plurality of symbol mappers 310, 312. Each symbol mapper 310, 312 maps data to one of a plurality of symbols included in the symbol constellation to produce a symbol stream corresponding to the modulated data. In one embodiment of the invention, the symbol mappers 310, 312 map data using a quadrature amplitude modulation (QAM) mapping scheme. However, the mapping scheme used is not critical to the present invention, and one of ordinary skill in the art realizes that many mapping schemes can be used here, such as binary phase shift keying (BPSK) or quadrature phase shift keying (QPSK), without departing from the spirit and scope of the present invention. After the symbol mappers 310, 312 modulate the data, the processor 206 passes the modulated data to the transmitter section 202 for transmission.

The transmitter section 202 includes a plurality of modulators 314, 316 connected to one of a plurality of amplifiers 318, 320, respectively. The transmitter part 202 further comprises a plurality of weighters 322 , 324 respectively connected between one of the plurality of amplifiers 318 , 320 and one of the plurality of antennas 121 , 122 and further connected to the processor 206 . Each modulator of the plurality of modulators 314, 316 receives modulated data from a respective symbol mapper 310, 312 and modulates the modulated data onto a radio frequency (RF) carrier. Thereafter, each modulated carrier is passed to an amplifier 318, 320 connected to a respective modulator 314, 316, which amplifies the modulated carrier, produces an amplified signal, and passes the amplified signal to a respective weighter 322, 324. Each weighter 322 , 324 modulates the amplified signal based on the weighting coefficients provided to the weighter by the processor 206 and transmits the amplified signal via the respective antenna 121 , 122 . In other embodiments of the invention, each weighter 322, 324 may be placed between the modulator 314, 316 and the amplifier 318, 320, or may be placed before the modulator 314, 316 and between the processor 206 Inside.

To optimize the strength of the RF signal received by the target MS (e.g., MS 110) from the BTS 104, 105 serving the MS, and to minimize communication of the RF signal with the BTS and other active MSs in the sector served by the BTS interference, each BTS 104, 105 transmits RF signals using beamforming techniques that switch beams. Switched beam beamforming techniques allow a BTS to send a narrowly focused signal to a target MS 110 based on the weighting coefficients assigned by the BTS to each component 121, 122 of the antenna array associated with the BTS.

Current and proposed Code Division Multiple Access (CDMA) communication systems, such as 1XEV-DV (Data and Voice) system and HSDPA (High Speed Downlink Packet Access) system, respectively include multiple communication channel. Among the channels there are shared communication channels, ie shared packet data channels, which can be shared between multiple MSs served by the same BSS. In compliance with the 1XEV-DV and HSDPA standards, communication system 100, and particularly scheduler 106, preferably uses carrier-to-interference (C/I) feedback from MSs to schedule usage of shared packet data channels by MSs 110-112. In scheduling operations on the shared packet data channel, the scheduler 106 considers (1) selecting which of a plurality of MSs to schedule for the shared packet data channel; (2) selecting an encoder packet size for the MS; and (3) Select several Walsh codes to be assigned to the MS. The shared packet data channel in 1xEV-DV can be code-division multiplexed between two users (2-user CDM), while the shared packet data channel of HSDPA can be code-division multiplexed between four users (4-user CDM ). Although the following discussion will only focus on 2-user CDM supported by 1xEV-DV, those of ordinary skill in the art realize that the concepts discussed are equally applicable to 4-user CDM scenarios.

C/I feedback may be determined as follows. Each of the plurality of MSs 110-112 measures the propagation channel between the MS and an array component of BSS 102 by correlating the signal received from the component with a known version of the signal. For example, BSS 102 may transmit a pilot code, such as a predetermined pilot Walsh code, or a sequence of pilot symbols assigned to a component known to the MS via the component. When the MS receives the transmitted signal, the MS correlates the received signal with known pilot codes or symbols. Thereafter, based on the comparison, the MS determines the symbol distortion due to the channel.

Measuring the autocorrelation of background noise is more difficult. In one embodiment of the invention, each MS 110-112 measures the autocorrelation of the background interference by demodulating the signal received from the BSS 102 and subtracting the demodulated signal from the arriving signal. The resulting signal includes only background interference, and the autocorrelation of this signal can be easily obtained by correlating the signal with itself. In another embodiment of the invention, the MS may measure the autocorrelation by the BSS 102 periodically blocking its transmitted signal for a short period of time. During the short period of time when the transmitted signal is turned off, the received signal includes only background interference. Furthermore, the autocorrelation of the interference can be measured by correlating the signal with itself.

In yet another embodiment of the invention, each MS 110-112 may measure the autocorrelation of the background interference by measuring the correlation of the received signal transmitted by the BSS 102 by correlating the signal with itself. The correlation is the sum of the signal correlation function and the interference correlation function. The MS sends the channel propagation information and the received signal correlation function to the BSS 102, i.e., the BTS serving the MS. The BSS 102, preferably the processor 206 of the BTS serving the MS, computes a signal correlation for the transmitted signal observed at the MS based on knowledge of the propagation channel and the transmitted signal (e.g., pilot signal). Thereafter, the interference correlation is obtained by subtracting the calculated correlation of the transmitted signal from the correlation function of the received signal.

Using knowledge of the propagation channel between each of the plurality of array components of the BSS 102 and each of the plurality of MSs 110-112 served by the BSS, and the interference environment at each MS, the BSS 102 assigns power to determining a signal-to-noise ratio (SNR) at each MS served by the BSS, and further determining a set of weighting coefficients from multiple sets of weighting coefficients, the multiple sets of weighting coefficients respectively corresponding to multiple a fixed beam. For example, the storage device 208 of the BTS serving the MS may store multiple sets of weighting coefficients, where each set of weighting coefficients in the multiple sets of weighting coefficients corresponds to one of the multiple beams associated with the sector served by the BTS. The processor 206 of the BTS then selects the set of weighting coefficients that yields the greatest SNR, although other criteria for selecting a set of weighting coefficients are known to those of ordinary skill in the art and may be used herein without departing from the spirit of the invention with range. When a BTS, such as BTS 104, subsequently transmits a signal to an MS served by the BTS, the processor 206 of the BTS transmits the appropriate weighting coefficients to the weighters 322, 324 of the BTS. Each weighter 322, 324 then uses the weighting coefficients communicated to the weighter by the processor 206 to modulate the signal transmitted through the corresponding antenna array component, which is then transmitted via the corresponding array component at a plurality of fixed, predetermined transmitted in the beam.

Referring now to FIG. 4, there is illustrated a block diagram of a sector 400 (eg, sectors 151-153) of communication system 100, in accordance with an embodiment of the present invention. Sector 400 includes a plurality of beams 401, 402 (two shown) that are transmitted by antenna arrays (eg, antenna arrays 120, 130, and 140) and BTS 104 associated with the sector. Similar to in 1xEV-DV, the air interface between the BTS of the serving sector and each of the MSs located in that sector (i.e., MS 110 and 111) includes a shared packet data channel that supports two-user code division multiplexing (CDM) and shared between two users or MSs.

In order to increase the capacity of the communication system 100, or to increase the number of users participating in the communication session at the same time, the communication system, especially the scheduler 106, schedules a different MS or user. By simultaneously scheduling users on each of the plurality of beams 401, 402, the performance and throughput of the communication system 100 is significantly increased relative to the prior art. In the first embodiment of the invention, only shared communication channels (eg, shared packet data channels) are used to communicate user information to MSs 110, 111 located in sector 400, and there is no 1X voice or data. Let _γ1,p denote the pilot C/I of a first MS (e.g., MS 110), which is located in a first beam (e.g., beam 401), and let _γ2,p denote the pilot C/I of a second MS (e.g., MS 111). Frequency C/I, which is located in a second beam (eg, beam 402). Let _NPDCH denote the number of Walsh codes allocated to the shared communication channel, let P denote the total transmit power allocated to sector 400, and let fo denote the total power allocated to overhead channels (e.g., pilot, paging, and synchronization channels) The coefficient (fraction).

To maintain the integrity of the C/I feedback, it is assumed that the power transmitted in each beam 401 and 402 is equal and constant. Thus, the power allocated to each beam 401 and 402 is P/2. In this way, the C/I information at each associated MS 110 and MS 111 is only a function of attenuation and not due to fluctuations in transmit power.

If only a single MS is scheduled at a certain moment in a certain sector, and the signal to that MS is sent on both beams of the sector (or only on the scheduled user's beam and on the other beam) CDMA noise of equal power), the maximum obtainable sector capacity is given by

$\mathrm{<span\; class="notranslate">\; Capacity</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; )</span>}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}}\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}}\mathrm{<span\; class="notranslate">\; max</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

where f _p is a coefficient of the transmit power allocated to the pilot channel. To simplify the representation, let

$\mathrm{<span\; class="notranslate">\; \&zeta;</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; )</span>}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}}\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}}$

Thus, when only a single MS is scheduled at a certain moment, and the signal intended for the MS is transmitted through both beams, the capacity of the sector is given by

Capacity＝N _PDCH log ₂ (1+ζmax(γ _1,p ,γ _2,p ))

In communication system 100, separate MSs or users are scheduled concurrently in each of multiple beams associated with a sector (ie, beams 401 and 402 of sector 400). When signals intended for MSs 110, 111 associated with sector beams 401, 402, respectively, are sent only on the beams associated with the MSs, the capacity of sector 400 is given by

$\mathrm{<span\; class="notranslate">\; Capacity</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&zeta;</span>}}{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&zeta;</span>}}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>$

where α represents the coefficients assigned to the Walsh code space of the first MS 110, and 1-α represents the coefficients assigned to the second MS 111. Note that in this formula, the power allocated to each Walsh code in the two beams 401 and 402 is different.

The maximum achievable capacity of sector 400 is given by the formula

Capacity=N _PDCH log ₂ (1+ζ(γ _1,p +γ _2,p )), and the capacity is

$\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; .</span>\mathrm{<span\; class="notranslate">\; p</span>}}}{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}}$

obtained when.

The capacity increase resulting from using 2-user CDM with switched beams is given by

Capacity Increase＝N _PDCH (log ₂ (1+ζ(γ _1,p +γ _2,p ))-log ₂ (1+ζmax(γ _1,p ,γ _2,p )))

$<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&zeta;</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&zeta;</span>}\mathrm{<span\; class="notranslate">\; max</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; .</span>$

If γ _1,p = γ _2,p , the capacity increase is given by (formula below)

$\mathrm{<span\; class="notranslate">\; Capacity\; Increase</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&zeta;</span>}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; <figure-callout\; id="1"\; label="p"\; filenames="A20038010083500321.png,A20038010083500331.png"\; state="\{\{state\}\}">p</figure-callout></span>}}}{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&zeta;</span>}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

And this corresponds to a 3dB increase in the signal-to-interference ratio (SIR) per Walsh code for a shared communication channel.

Note that this is not a doubling of capacity. To double capacity at a 3dB increase in SIR also requires doubling the number of Walsh codes (and more generally, bandwidth). This can be done by allowing the use of quasi-orthogonal functions (QOFs, already in the CDMA 2000 1X standard) for packet data channels, where each beam 401, 402 is assigned a set of QOFs.

As a result, sector 400 capacity becomes comparable to concurrent A function of the sum of the SIRs of each of the scheduled MSs (ie, MSs 110 and 111), rather than the maximum of the two SIRs. Further, scheduling separate MSs or users in each beam 401 and 402 provides the additional benefit of a communication system that is compatible with C/I feedback, Adaptive Modulation and Coding (AMC), and scheduler 106 without in-phase Interference variations are introduced in neighboring sectors or cells.

In another embodiment of the invention, the system 100 may be a CDMA 1XEV-DV system in which the BSS 102 transmits user information to each of the MSs 110-112 served by the BSS via packet data channels and voice and data channels . 1X voice and data are not transmitted on the packet data channel and require some factor of the total transmit power in each of beams 401 and 402, and a factor of the total bandwidth. Also, the power required to provide 1X voice and data services in the two beams is different. Let _f1 and _f2 denote coefficients of power allocated to CDMA 2000 1X voice and data (including pilot, paging, and synchronization overhead) in beams 401 and 402, respectively. For example, let f ₁ =1/3 and f ₂ =2/3. As above, let _NPDCH denote the number of Walsh codes available for the packet data channel. Note that this number does not include Walsh codes for overhead channels (eg, pilot, paging, and synchronization channels) and Walsh codes allocated for IX voice and/or data.

Without CDM, when only a single MS or user is scheduled to receive an information signal, and that signal is sent on both beams (or only on the scheduled MS's beam and equal power CDMA noise on the other beam) ), the maximum capacity available to the sector is given by the following formula

Capacity=N _PDCH log ₂ (1+ζmax((1-f ₁ )γ _1,p , (1-f ₂ )γ _2,p )),

where ζ is defined as above.

Referring again to FIG. 4, in communication system 100, separate MSs or users are concurrently scheduled in each of the plurality of beams associated with a sector (ie, beams 401 and 402 of sector 400). That is, a first MS (eg, MS 110) is scheduled to receive information signals via a first beam (eg, beam 401), and a second MS (eg, MS 111) is scheduled to receive information signals via a second beam (eg, beam 402). Further, information signals intended for a particular MS are only sent to the MS on the associated beam. The capacity of sector 400 is given by the following formula

$\mathrm{<span\; class="notranslate">\; Capacity</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&zeta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&zeta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>$

where α represents the coefficient of the N _PDCH Walsh codeword assigned to the first MS 110 in the first beam 401 and 1−α represents the coefficient of the codeword assigned to the second MS 111 in the second beam 402 . The maximum achievable capacity is given by the formula

Capacity=N _PDCH log ₂ (1+ζ((1-f ₁ )γ _1,p +(1-f ₂ )γ _2,p )),

and the capacity is

$\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}}$

obtained when.

In this way, switching beams provides similar advantages in hybrid systems with both IX voice and data and shared communication channels as using only shared communication channels. As above, the scheduling of separate users for each of the plurality of exchanged beams results in a sector capacity that is a function of the sum of the SIRs of each of MS 110 and MS 111, a function of the beam power available for the shared communication channel The coefficients are proportional, not a function of the maximum value of the two SIRs. Moreover, scheduling separate MSs or users in each beam 401 and 402 provides the additional benefit of a communication system that is compatible with C/I feedback, Adaptive Modulation and Coding (AMC), and scheduler 106 without being in adjacent Interference variations are introduced in a sector or cell.

The result of the scheduling of separate users for each of multiple switched beams is directly extendable to systems supporting multiple beams per sector and/or supporting more than two CDM users per sector. As noted above, HSDPA supports 4-user CDM, and the ideas expressed here are directly applicable to HSDPA. For example, with four switching beams in a sector and 4-user CDM supported by HSDPA, the SIR increase per Walsh code can be up to 6dB.

In yet another embodiment of the invention, the scheduling of separate users for each of the plurality of switched beams can be extended to support code division multiplexed shared communication channels of more than two users, such as HSDPA shared packet data channels. Figure 5 is a block diagram of a sector 500 of the communication system 100, in accordance with another embodiment of the present invention. As shown in Figure 5, sector 500 includes three beams 501-503. Let _γ1,p denote the pilot C/I of a first MS (e.g., MS 110), which is located in the first beam 501, and γ2 _,p denote the pilot C/I of a second MS (e.g., MS 111), which is located in the second beam 502, and γ3 _,p represents the pilot C/I of a third MS (eg, MS 112), which is now located in the third beam 503, which is in the same cell as MSs 110 and 111.

As above, let _NPDCH denote the number of Walsh codes allocated to the shared communication channel (preferably the shared packet data channel sent on each air interface 116-118). Let P denote the total transmit power allocated to a sector. Let f _o denote a coefficient of the total power allocated to overhead channels (eg, pilot, paging, and synchronization channels). The power allocated to each beam is constant and equal to P/3. In this way, the C/I information at each MS 110-112 located within each beam 501-503 is only a function of attenuation and not due to fluctuations in transmit power.

If only a single MS is scheduled for a sector at a certain moment, and the signal is transmitted on all three beams (or only on the scheduled user's beam, and equal power CDMA noise is transmitted on other beams), the sector The maximum capacity achievable is given by the formula

$\mathrm{<span\; class="notranslate">\; Capacity</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; )</span>}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}}\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}}\mathrm{<span\; class="notranslate">\; max</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>$

=N _PDCH log ₂ (1+ζmax(γ _1,p ,γ _2,p ,γ _3,p )), where _fp and ζ are defined as above.

In the embodiment of communication system 100 shown in FIG. 5, separate MSs 110-112 are scheduled in each beam 501-503 in sector 500, respectively. Further, information signals intended for MSs 110-112 located in beams 501-503, respectively, are transmitted on that beam only. At this point, the capacity of sector 500 is given by the following formula

$\mathrm{<span\; class="notranslate">\; Capacity</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&zeta;</span>}}{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&zeta;</span>}}{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&zeta;</span>}}{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>$

where α is the coefficient of the Walsh code assigned to beam 501 , β is the coefficient of the Walsh code assigned to beam 502 , and 1-α-β is the coefficient of the Walsh code assigned to beam 503 . The maximum achievable capacity of sector 500 is given by

Capacity＝N _PDCH log ₂ (1+ζ(γ _{1, p} + γ _{2, p} + γ _{3, p} )), and the capacity is

$\mathrm{\&alpha;}=\frac{{\mathrm{\&gamma;}}_{1,p}}{{\mathrm{\&gamma;}}_{1,p}+{\mathrm{\&gamma;}}_{2,p}+{\mathrm{\&gamma;}}_{3,p}}$ and $\mathrm{\&beta;}=\frac{{\mathrm{\&gamma;}}_{2,p}}{{\mathrm{\&gamma;}}_{1,p}+{\mathrm{\&gamma;}}_{2,p}+{\mathrm{\&gamma;}}_{3,p}}$

obtained when.

Although described above with reference to three beams 501-503 in sector 500, those of ordinary skill in the art appreciate that the above improvement in system capacity obtained by concurrently assigning separate beams to each of a plurality of MSs can be easily can be extended to any number of beams in the cell 500.

In another embodiment of the present invention, the shared communication channel can support code division multiplexing of more than two MSs or users and operate in a system with CDMA 2000 1X voice and data. In particular, it is assumed that the shared communication channel supports code division multiplexing of three MSs or users 110-112, although one of ordinary skill in the art appreciates that this result can be easily extended to any number of MSs or CDM users.

1X voice and data are not sent on a shared communication channel and require some factor of the total transmit power in each beam and a factor of the total bandwidth. Referring again to FIG. 5, let f ₁ , f ₂ , and f ₃ represent the power allocated to CDMA 2000 1X voice and data (including pilot, paging, and synchronization channel overhead) in beams 501, 502, and 503, respectively. coefficient. As before, let _NPDCH denote the number of Walsh codes allocated to the shared communication channel. Note that this number does not include Walsh codes for overhead channels (eg, pilot, paging, synchronization channels), and Walsh codes allocated for IX voice and/or data.

Without CDM, when only a single user is scheduled in the sector to receive the user information signal, and the signal is sent on all three beams (or only on the scheduled user's beam, and equal power on other beams CDMA noise), the maximum available capacity of the sector is given by the following formula

Capacity=N _PDCH log ₂ (1+ζmax((1-f ₁ )γ _1,p , (1-f ₂ )γ _2,p , (1-f ₃ )γ _3,p )),

where ζ is defined as above.

With CDM, as shown in FIG. 5, separate MSs or users 110-112 may be scheduled in each of the three beams 501-503 in the sector 500. Additionally, information signals intended for each MS 110-112 are transmitted only on the beam associated with that MS. At this point, the capacity of sector 500 is given by the following formula

$\mathrm{<span\; class="notranslate">\; Capacity</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}\left(\begin{array}{c}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&zeta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&zeta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span>\\ <span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; \&zeta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span>\end{array}\right)$

where α is the coefficient of the Walsh code assigned to beam 501 , β is the coefficient of the Walsh code assigned to beam 502 , and 1-α-β is the coefficient of the Walsh code assigned to beam 503 as before. The maximum achievable capacity of sector 500 is given by the formula

Capacity=N _PDCH log ₂ (1+ζ((1-f ₁ )γ _1,p +(1-f ₂ )γ _2,p +(1-f ₃ )γ _3,p )),

and the capacity is

$\mathrm{\&alpha;}=\frac{(1-f_1){\mathrm{\&gamma;}}_{1,p}}{(1-f_1){\mathrm{\&gamma;}}_{1,p}+(1-f_2){\mathrm{\&gamma;}}_{2,p}+(1-f_3){\mathrm{\&gamma;}}_{3,p}},$ and

$\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}}$

obtained when.

In this way, switching beams provides similar advantages in hybrid systems with both IX voice and data and shared communication channels as using only shared communication channels.

Referring now to FIG. 6, another embodiment of the present invention is described wherein a sector 600 of the communication system 100 is divided into K beams 601-603, where K is greater than two. Ditto for marking. Let γi _,p denote the C/I of the MS or user associated with beam i (the user with the highest C/I in the beam, or the user selected by some other criterion), e.g. MS or user 110 in beam 601 The C/I. Let ζ be defined as above such that

$\mathrm{<span\; class="notranslate">\; \&zeta;</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; )</span>}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}}\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}}$

where P is the total power allocated to the sector, f _p is the coefficient of this power allocated to the pilot (channel), N _PDCH is the number of Walsh codes allocated to the shared communication channel, and f _o represents the allocation to the overhead channel ( For example, the power of pilot, paging and synchronization channels).

Let _fi denote the coefficient of the total power allocated to beam i that is currently allocated to voice and 1X data in the beam. It is assumed that the transmit power is always equally divided over the K beams 601-603 such that the power per beam is P/K.

When CDM is not used, if only a single user is scheduled in the sector to receive the user information signal, and the signal is sent on all three beams (or only on the scheduled user's beam and equal power on other beams CDMA noise), the maximum achievable capacity of the sector is given by

Capacity=N _PDCH log ₂ (1+ζmax((1-f ₁ )γ _1,p , (1-f ₂ )γ _2,p ,...,(1-f _K )γ _K,p ))

And this maximum capacity is achieved under the condition that we schedule the use of ^the shared packet data channel by user i ^* such that the product (1-f _i )γ _i,p is maximized and assign All Walsh codes N _PDCH and available power (1-f _i* ) P/K.

When using 2-user CDM, the maximum capacity achievable by the sector is given by the following formula

$\mathrm{<span\; class="notranslate">\; Capacity</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; PDCH</span>}}{\mathrm{<span\; class="notranslate">\; log</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&zeta;</span>}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{{\mathrm{<span\; class="notranslate">\; i</span>}}^{<span\; class="notranslate">\; *</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{{\mathrm{<span\; class="notranslate">\; i</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{{\mathrm{<span\; class="notranslate">\; j</span>}}^{<span\; class="notranslate">\; *</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{{\mathrm{<span\; class="notranslate">\; j</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

where i ^* and j ^* are two MSs or users (associated with beams i ^* and j ^* ), such as MSs 110 and 111 located in associated beams 601 and 602 in sector 600, such that the product (1− f _i )γ _i,p is the largest and the capacity is obtained when the coefficient α of the N _PDCH Walsh code assigned to MS (beam) i ^* is given by

${\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{{\mathrm{<span\; class="notranslate">\; i</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{{\mathrm{<span\; class="notranslate">\; i</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{{\mathrm{<span\; class="notranslate">\; j</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}}<span\; class="notranslate">\; ,</span>$

And the coefficient of the Walsh code assigned to MS (beam) j ^* is (1-α).

If MSs or users k and l are scheduled (not necessarily MSs or users i ^* and j ^* ), the maximum capacity achievable is given by

Capacity=N _PDCH log ₂ (1+ζ((1-f _k )γ _k,p +(1-f _l )γ _l,p )),

And this capacity is only obtained under the condition that N _PDCH is allocated to MS k and the remaining coefficient (1-α) is allocated to MS l, where α is given by (the following formula)

$\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; p</span>}}}$

In other embodiments of the invention, the communication system 100 may allocate other uses to beams that do not include MSs or users that are currently allocated to shared communication channels to optimize system capacity. In one such embodiment, the portion of the shared communication channel assigned to one of the neighbor beams of such a beam may be transmitted in this beam using power equal to the power available to the packet data channel in this beam. In another such embodiment, the entire shared control channel, i.e. the shared packet data control channel, (the sum signal of the two CDM users) may be transmitted on such a beam using a power equal to the available power of the packet data channel in this beam. gained power. In yet another such embodiment, unused Walsh codes may be used to transmit a randomly modulated bit stream in such a beam using power equal to the power available to the packet data channel in this beam.

In another embodiment of the present invention, when the communication system 100 is a CDMA 2000 1xEV-DV communication system including a plurality of control channels, such as a first packet data control channel (PDCCH) and a second packet data control channel (PDCCH) , the first PDCCH may be sent to all (and only) such beams where the MS is currently assigned to the shared packet data channel (PDCH). The second PDCCH then transmits only beams whose target users are for this second PDCCH.

In yet another embodiment of the present invention, the communication system 100 may transmit CDMA noise (randomly modulated unused Walsh codes) on the shared communication channel to keep the transmit power in each beam equal and constant and maintain C/ Integrity of I Feedback. The transmission of noise may be desirable as long as there is no data to transmit on the shared communication channel during certain time intervals, or there are two beams for the shared packet data channel but four beams for 1X voice and data. In this case, only two of the four beams can be modulated for the shared communication channel, the other two beams must be filled with noise.

In another embodiment of the invention, it may be desirable to assign different coefficients of the sector's total transmit power (rather than equal power) to the beams. This method may be useful when the average traffic is not evenly distributed among the beams. For the same reason that a service has traffic requirements with a non-uniform angular distribution, it may also be desirable to use beams of different widths. Both techniques can also be combined, ie the power levels of the beams can be unequal and the widths of the beams can be unequal. In all cases, the allocation of Walsh codes between users in different beams can be allocated so as to maximize theoretical capacity in a manner similar to that given above. More specifically, the power per beam can be maintained at an approximately fixed level while allocating Walsh codes for the shared packet data channel in order to maximize capacity. Preferably, although the power distribution between beams may not be equal, the power level of the beams should be kept approximately constant in order not to corrupt the C/I feedback from the mobile (station). If the power levels of the beams change, they should change infrequently, or at a low rate, because changing these power levels destroys the C/I feedback.

In summary, to increase capacity, i.e., the number of MSs or users participating in concurrent communication sessions, the communication system 100 schedules a different MS or user. By simultaneously scheduling users in each of the multiple beams, the performance and throughput of the communication system 100 is significantly increased over the prior art. In one embodiment of the invention, a portion of a communication channel (eg, a shared packet data channel) shared between multiple MSs located in a sector is allocated to each MS scheduled in a beam. The portion of the shared communication channel allocated to each MS is thereafter transmitted concurrently to the MS via the beam associated with the MS. In other embodiments of the present invention, wherein one or more MSs located in the sector share the shared communication channel, while other MSs located in the sector do not utilize the shared communication channel, the communication channel sent to the latter MS can be Noise is transmitted in a portion of the shared communication channel. In other embodiments of the invention, the voice channel, data channel and control channel associated with each MS scheduled in a beam may be sent to each MS concurrently via the beam associated with the MS. In other embodiments of the invention, the communication system 100 may distribute the total transmit power allocated to a sector approximately equally among the plurality of beams associated with the sector, or at unequal ratios among the plurality of beams. way distribution. By individually adjusting the power of the signal transmitted in each beam, the quality of the received signal can be optimized and interference caused by the transmission of signals in multiple beams in the same sector can be minimized.

7 is a logic flow diagram 700 of steps performed by the communication system 100 in transmitting information to each of a plurality of MSs 110, 111 via a switched beam antenna system. When the communication system 100, preferably the scheduler 106, schedules (702) a plurality of MSs located in a particular sector served by the BSS (e.g. MSs 110-111 located in the sector 151 served by the BSS 102 (two are shown) ) for a different MS in each of the plurality of beams 160, 161 (two shown) associated with the sector, the logic flow diagram 700 begins. For example, a first MS 110 of the plurality of MSs 110, 111 may be scheduled for the first beam 160 and a second MS 111 of the plurality of MSs 110, 111 may be scheduled for the second beam 161. The BSS 102 communicates with each of the plurality of MSs 110, 111 via respective air interfaces 116, 117. When each air interface 116, 117 includes a shared communication channel, such as a shared packet data channel, the communication system 100, preferably the BSS 102, allocates (704) a first portion of the shared communication channel to the first MS 110 and assigns the shared A second portion of the communication channel is allocated (706) to the second MS 111. The BSS 102, in particular the BTS serving each MS, thereafter transmits (708) the first portion of the shared communication channel to the first MS 110 in the first beam 160 and to the second MS 111 in the second beam 161 ( 710) The second part of the shared communication channel.

When the communication system 100 is a CDMA communication system, the shared communication channel may include multiple orthogonal codes. In such a situation, the step of allocating (704) the first portion of the shared communication channel to the first MS 110 may include allocating to the first MS 110 a first set of orthogonal codes of a plurality of orthogonal codes, while the shared The step of assigning (706) the second portion of the communication channel to the second MS 111 may include assigning to the second MS 111 a second set of the plurality of orthogonal codes. The step of sending (708, 710) the first and second portions of the shared communication channel to the first and second MS 110, 111 in each MS's respective beam 160, 161 includes sending (708, 710) the first and second portions of the shared communication channel to the first MS in the first beam 160, respectively. The MS 110 sends the first set of orthogonal codes and the step of sending the first set of orthogonal codes to the second MS 111 in the second beam 161. The first group of orthogonal codes and the first group of orthogonal codes may respectively include the same part of the plurality of orthogonal codes, or may respectively include different parts of the plurality of orthogonal codes.

In another embodiment of the invention, the communication system 100, i.e. each air interface 116, 117 between the BSS 102 and the MSs 110 and 111, may further comprise a control channel, preferably a packet data control channel. In such an embodiment, the logic flow 700 may further include sending, by the BTS 104, 105 serving each MS, to the first MS 110 in the first beam 160 and the second MS 111 in the second beam 161, respectively (712) Steps to control the channel. In yet another embodiment of the present invention, the communication system 100 may further include multiple control channels, preferably multiple packet data control channels. In such an embodiment, the step of sending (712) the control channel by the BTS serving each MS to the first MS 110 in the first beam 160 and the second MS 111 in the second beam 161, respectively, may include The beams 160 and 161 transmit the first control channel of the plurality of packet data control channels to the first MS 110 and the second MS. The logic flow 700 may thereafter further include the step of transmitting (714) a second control channel of the plurality of control channels in the first beam 160, but not in the second beam 161, by the BTS serving each MS.

In yet another embodiment of the present invention, communication system 100, ie, each air interface 116, 117 between BSS 102 and MSs 110 and 111, may further include a plurality of voice channels and a plurality of data channels. In such an embodiment, the logic flow 700 may further include sending (716), by the BTS serving the MS, the first voice channel of the plurality of voice channels and the first of the plurality of data channels to the MS 110 in the first beam 160. data channel, and the step of sending (718) a second voice channel of the plurality of voice channels and a second data channel of the plurality of data channels by the BTS of the serving MS to a second MS 111 in the second beam 161. In yet another embodiment of the invention, the logic flow 700 may further (include) transmitting (720) by the BTS serving the MS in a third beam of the plurality of beams associated with the sector 151 one of the plurality of voice channels A third voice channel and a third data channel of the plurality of data channels, and the step of transmitting (722) noise in a portion of a shared communication channel associated with a third beam.

In other embodiments of the invention, different proportions of the total transmit power allocated to a sector 151 may be allocated to each of the plurality of beams 160, 161 associated with that sector. For example, in one embodiment of the invention, the BSS 102 or the BTS serving each MS may allocate (724) the same proportion of the total transmit power allocated to the sector 151 to each of the plurality of beams 160, 161. When the sets of orthogonal codes transmitted in each beam are of different sizes, a consequence of allocating the same proportion of the total transmit power to each of the multiple beams may be to allocate different transmit power to each orthogonal code. However, it is not necessary to allocate the same proportion of the total power to each beam, and in another embodiment of the invention, the BSS 102 or the BTS serving each MS may allocate a different proportion of the total transmit power allocated to the sector 151 ( 726) to each of the plurality of beams 160,161.

By scheduling different MSs or users in each of the multiple beams associated with a coverage area (particularly a sector), the communication system 100 increases capacity, i.e. mobile stations (MSs) participating in concurrent communication sessions or the number of users. Each of a plurality of MSs located in a coverage area, preferably a sector, is scheduled for a different one of a plurality of beams associated with the sector. By simultaneously scheduling each of the plurality of MSs in each of the plurality of beams, the performance and throughput of the communication system are significantly increased over the prior art. Further, by simultaneously scheduling each of the plurality of MSs in each of the plurality of beams, each of the MSs scheduled in the beam can be concurrently transmitted to the plurality of MSs via the beam associated with each MS. MS associated shared communication channels, voice channels, data channels, and control channels. Additionally, the power of signals transmitted in each beam can be individually adjusted to optimize the quality of received signals and minimize interference caused by transmission of signals in multiple beams in the same sector.

While the invention has been shown and described with reference to particular embodiments thereof, it will be understood by those skilled in the art that various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention as set forth in the appended claims. Accordingly, the specification and drawings are to be regarded as illustrative rather than restrictive, and all such modifications and substitutions are intended to be included within the scope of the present invention.

Benefits, other advantages, and solutions to problems have been described above with reference to specific embodiments. However, benefits, advantages, solutions to problems, and any one or more components that may cause any benefit, advantage, or solution to occur or become more significant should not be construed as decisive, essential to any claim or essential features or components. As used herein, the term "comprises" or any other variation thereof is intended to refer to a non-exclusive inclusion such that a process, method, article, or apparatus comprising a list of components includes not only those listed components, but also includes Other components not specifically listed or inherent to such process, method, article or apparatus.

Claims (16)

1. in comprising a plurality of mobile radio stations and a kind of communication system that exchanges beam antenna system, wherein said exchange beam antenna system comprises architecture and a plurality of wave beam, described a plurality of wave beam is used for sending user profile to described a plurality of mobile radio station from described architecture, a kind of method, it is used for user profile is sent to each mobile radio station of described a plurality of mobile radio stations, described method comprises step: dispatch the different mobile radio stations in described a plurality of mobile radio station, to use each wave beam in described a plurality of wave beam basically simultaneously.

2. the method for claim 1, wherein, first mobile radio station in described a plurality of mobile radio station is included in first wave beam in described a plurality of wave beam, wherein, second mobile radio station in described a plurality of mobile radio station is included in second wave beam in described a plurality of wave beam, and wherein, described communication system further comprises shared communication channel, and wherein, described method further may further comprise the steps:

Distribute the first of described shared communication channel to described first mobile radio station;

Distribute the second portion of described shared communication channel to described second mobile radio station;

In described first wave beam, send the described first of described shared communication channel; With

In described second wave beam, send the described second portion of described shared communication channel.

3. method as claimed in claim 2, wherein, described communication system further comprises control channel, and wherein, described method further comprises step: send described control channel in each in described first wave beam and described second wave beam.

4. method as claimed in claim 3, wherein, described control channel comprises first control channel, wherein, described communication system further comprises second control channel, and it is associated with described first mobile radio station, and is not associated with described second mobile radio station, and wherein, described method further comprises step: in described first wave beam but send described second control channel in described second wave beam.

5. method as claimed in claim 2, wherein, described communication system further comprises a plurality of voice channels and a plurality of data channel, and wherein, described method further may further comprise the steps:

First voice channel in described first wave beam in the described a plurality of voice channels of transmission and first data channel in described a plurality of data channel; With

Second voice channel in described second wave beam in the described a plurality of voice channels of transmission and second data channel in described a plurality of data channel.

6. method as claimed in claim 5, it further may further comprise the steps:

The 3rd voice channel in the 3rd wave beam in described a plurality of wave beams in the described a plurality of voice channels of transmission and the 3rd data channel in described a plurality of data channel; With

Transmitted noise in the part of the shared communication channel that is associated with described the 3rd wave beam.

7. the method for claim 1, wherein described communication system is divided into a plurality of geographic sector area, and wherein, each wave beam in described a plurality of wave beams sends in the same sector in described a plurality of sectors.

8. in the communication system that comprises the exchange beam antenna system that generates a plurality of predetermined, fixing wave beams, a kind of base station sub-system, it comprises:

Aerial array, it comprises a plurality of array components;

A plurality of weighter, wherein, each weighter in described a plurality of weighter is connected to an assembly in described a plurality of assembly; With

Processor, it is connected to each weighter in described a plurality of weighter, wherein, described processor sends first group of weight coefficient to described weighter, information is sent to first mobile radio station in a plurality of mobile radio stations, and further send second group of weight coefficient to described weighter, information is sent to second mobile radio station in described a plurality of mobile radio station, wherein, described weighter utilizes described first group of weight coefficient to come to send first wave beam in described a plurality of wave beam to described first mobile radio station, and wherein, described weighter utilizes described second group of weight coefficient to come to send second wave beam in described a plurality of wave beam to described second mobile radio station.

9. base station sub-system as claimed in claim 8, it further comprises scheduler, it distributes described first wave beam to described first mobile radio station, and distributes described second wave beam to described second mobile radio station.

10. base station sub-system as claimed in claim 8, wherein, described processor comprises the spreading code maker, it generates first group of spreading code, in described first wave beam, information sent to described first mobile radio station, and it further generates second group of spreading code, information sent to described second mobile radio station in described second wave beam.

11. base station sub-system as claimed in claim 8, wherein, described base station sub-system sends the first at least of shared communication channel in described first wave beam, and sends the second portion at least of described shared communication channel in described second wave beam.

12. base station sub-system as claimed in claim 11, wherein, described base station sub-system further transmits control channel in each in described first wave beam and described second wave beam.

13. base station sub-system as claimed in claim 12, wherein, described control channel comprises first control channel, and wherein, and described base station sub-system is further at described first wave beam but do not send second control channel in described second wave beam.

14. base station sub-system as claimed in claim 11, wherein, described base station sub-system further sends first voice channel in a plurality of voice channels and first data channel in a plurality of data channel in described first wave beam, and sends second voice channel in described a plurality of voice channels and second data channel in described a plurality of data channel in described second wave beam.

15. base station sub-system as claimed in claim 14, wherein, described base station sub-system further sends the 3rd voice channel in described a plurality of voice channels and the 3rd data channel in described a plurality of data channel in the 3rd wave beam in described a plurality of wave beams, and in the part of the described shared communication channel that is associated with described the 3rd wave beam transmitted noise.

16. base station sub-system as claimed in claim 8, wherein, described base station sub-system operates in the communication system that is divided into a plurality of geographic sector area, and wherein, each wave beam in described a plurality of wave beams sends in the same sector in described a plurality of sectors.

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