CN1280751A - Method and arrangement for generation of cell relations in a mobile communications by system - Google Patents

Abstract

This invention discloses a mobile communication system and method for determining cell relationships between cells. The invention utilizes strongly encoded predefined messages transmitted from the MS (or BS) and received by multiple radio ports. Measurement results of the received messages are reported to a central unit for processing and/or storage. The central unit commands the transmission and reception of the predefined messages. The central unit also clears interference on a certain frequency to ensure reliable reception by remote receivers.

Description

Method and device for generating cell relationship in mobile communication system

field of invention

The present invention relates generally to wireless communication systems, and more particularly to a method and system for measuring cell relationships in a cellular communication system.

Background of the invention

Usually, for a cellular wireless communication system, radio resources are divided over the entire system coverage area. The principle of the cellular system is to divide a coverage area into several sub-areas, namely cells, where each cell has a set of available communication resources to serve users. There are many known techniques for dividing available radio resources between cells. In a TDMA system (Time Division Multiple Access), users are allowed to send information in time slots on a radio frequency carrier, so that different time slots are assigned to individual users on the same frequency. For example, in such a system, channels between cells may be divided such that adjacent cells use different frequencies. There are two types of interference: co-channel interference and adjacent channel interference; these interferences are limited by the intelligent division of radio resources between coverage areas (ie, cells). Co-channel interference occurs when two separate signals are transmitted on the same frequency at the same time. The individual signals will interfere with each other, and a receiver receiving both signals may not be able to separate one signal from the other or detect either of them. Adjacent channel interference occurs if spectrally adjacent channels are used within the same geographic area. Transmissions on one frequency can leak into adjacent channels and cause interference. These problems can be limited by intelligently allocating frequencies to different coverage areas. But there is still some (co-channel) interference between different cells, mainly because frequencies have to be reused. But cell planning can be improved if the cell relationships are known and this unavoidable interference will be more limited.

In addition, if it is known how much interference is susceptible to on a certain channel, and where (in which cell) the interference occurs, an improved channel allocation algorithm can be implemented. Therefore, using slow and fast information about how a new connection will affect existing connections will further improve the allocation algorithm. Known methods of estimating cell relationships focus on measuring the total interference of a certain cell. Measurements are usually performed on the normal traffic of the system, and therefore the measurement of cell relations cannot be controlled in an efficient manner. Furthermore the measurements are limited to interference estimation and estimation of the signal strength of ongoing traffic and signaling (which is usually itself susceptible to interference). The radio head is not allowed to receive signals from distant cells because the carrier-to-interference (C/I) ratio is not sufficient for highly reliable detection. In addition, in the cellular system, the earlier method estimated the path gain based on statistical measurement, which generated a lot of signaling from the base station, and also introduced unnecessary traffic into the system.

An adaptive wireless communication system is described in US Patent No. 5,157,709. The system includes a control station supporting the jamming matrix. This matrix represents the received signal path gain values over the wireless channel. This information is used for adaptive channel allocation. Another method of estimating interference is described in U.S. Patent No. 5,603,092. In both patents the measurements are performed during the course of the transaction. Simultaneously measuring signals from several transmitters often results in only the strongest signal being identified. If all pairs of cells that may interfere with each other work on the same frequency channel, it is important to find the cell relationship between them. The signal from some of these cells was very weak, and it was difficult to decode the original content of the signal.

It would therefore be advantageous to provide a method of reliably estimating the cell relationship of even distant (non-adjacent) cells without interfering with or being disturbed by ongoing traffic And a lot of signaling will not be generated between the base station and the system.

Summary of the invention

Problems often arise due to insufficient carrier-to-interference ratio (C/I) when measuring the cell relationship of cells that are far apart from each other.

The above and other problems are solved according to the invention by ordering the transmitter to send specific, predefined messages mainly for measurement purposes and ordering one or several receivers to measure the received signal strength.

In more detail, the problem is solved by ordering a transmitter to transmit a message on a certain frequency for a certain time, and ordering at least one receiver to measure the signal strength of the message and to report said measured signal strength to a central unit signal strength. Statistical cell relation values representing path gains from transmitters to receivers are generated at the central unit.

Specific, pre-defined messages can be strongly encoded to allow their detection in harsh wireless environments and in remote receivers. Additionally, in one embodiment of the invention, the central unit may send a silence request, ie, order other transmitters not to transmit on a certain frequency and for a certain period of time. This will also reduce interference on that frequency and allow even further distant receivers to detect this particular, pre-defined message.

In another embodiment, prior to channel allocation, the mobile station can transmit a specific, predefined message on the frequency to be allocated, and thereafter the transceiver station (e.g. radio head) can estimate a certain frequency allocated for a new connection. channels that add additional interference to connections already in the system. This information is readily available and possibly combined with the obtained statistical information in order to use it eg in Adaptive Channel Allocation (ACA) algorithms, admission control (adminssion control) or control algorithms.

In another embodiment of the invention, a specific frequency is used to transmit predefined messages from a single radio head and signal strength measurements are made in mobile stations not in the cell served by the transmitting radio head. For a given limited geographic area, this specific frequency is only used for predefined messages. These measurements are combined with mobile measurements of the signal strength on the current serving frequency within the cell and another cell relationship measure, C/I, can be calculated. When the mobile station is making measurements, the single radio head is the only transmitter on that particular frequency for a limited time, and the other radio head also becomes the only transmitter on that particular frequency. Repeated measurements will provide cell relationships for all cell pairs in the form of C/I.

It is an object of the present invention to be able to obtain reliable cell relationships also between cells that are far apart.

Another object of the invention is to obtain short-term information about the current interference situation.

Yet another object of the invention is to obtain frequent measurements and collect the measured information for statistical purposes.

An advantage of the present invention is that not only cell relations of cells that are close to each other can be obtained.

Another advantage is that the current situation can be analyzed eg before the mobile station starts to transmit.

Yet another advantage is that statistical measures of cell relationships can be obtained over a large area.

Brief description of the drawings

The present invention will be more fully understood when read in conjunction with the detailed description in conjunction with the accompanying drawings in which like reference numerals are used to designate like elements, in which;

Figure 1 shows signaling between a central unit, radio heads and mobile stations according to one embodiment of the invention.

Figure 2 is a representative diagram of an indoor system embodying the present invention.

Figure 3 is a representative diagram of a (macro) cell implementing the invention.

Figure 4 represents a path gain matrix in which measurements according to the invention can be stored.

FIG. 5 is a flow chart describing an exemplary embodiment of the present invention.

FIG. 6 is a flowchart describing another exemplary embodiment of the present invention.

Fig. 7 illustrates an exemplary embodiment of the invention in which measurements are performed by a mobile station.

A detailed description

The present invention will be described below with respect to a centralized synchronization type cellular mobile communication system employing a time division multiple access (TDMA) scheme. But it should be understood that other synchronous types and asynchronous systems of the same or other access types are also contemplated by the present invention. Packet switched systems as well as circuit switched systems can use the invention.

According to an aspect of the invention, a transmitter (eg, a mobile station) transmits a predefined message on a traffic channel, which message may be received by multiple radio heads. The predefined messages are also explained below. A radio head is defined here as a base station or other type of transceiver station directly or indirectly connected to a mobile switching center or corresponding equipment. A typical radio head is a base station serving a specific cell in a cellular radio system. For distributed indoor systems, the radio head is a transceiver station serving a part of a cell, a sub-cell, many of which form a cell. The radio head is able to measure several parameters of this particular predefined message, like for example received signal strength, delay spread, mobile identity (if included in the predefined message) and signal to interference ratio (carrier to interference ratio C/I). In one embodiment the radio head receiving the predefined message will measure the signal strength and report the measurement to the central unit where the signal strength measurement is used to calculate the path gain between the cell sending the message and the cell receiving the message. This is possible if predefined messages are sent with a certain transmit power. The central unit (or radio head) can order the MS to send the predefined message with a certain power, or the MS can contain information about the power value used for the predefined message. The measurement results can of course be used to calculate other types of cell relationships and path gain is an example. Path gain is nothing but the relationship between transmitted power and received power. The processing of the path gain can instead be performed at each radio head, in which case its result is reported to the central unit. This is an ongoing process. The statistical representation of the obtained measurement results may be expressed, for example, in the form of a distribution function.

These measurements can be stored in a path gain matrix and used later in several applications when inter-cell relationships are required. It may be applied in an adaptive channel allocation algorithm, may be applied in a handover algorithm or used for access control, for example for cell planning purposes.

Figure 1 shows an embodiment of the present invention. The figure shows a mobile telecommunications system. In order to make the diagram clearer, Fig. 1 removes many of the elements involved in a complete telecommunication system. Figure 1 illustrates only those elements in a public land mobile network which are necessary for understanding the invention. The central unit CU is connected to several radio heads or base stations. The connection from the central unit to the wireless head BS1 is indicated by dashed lines. The radio head BS1 can establish radio connections with mobile stations located within the radio coverage of the base station. In the figure, a zigzag symbol is used to indicate the wireless connection between the wireless head BS1 and the mobile subscriber MS.

The method according to the invention comprises the following steps:

- The central unit CU instructs the measurement equipment of each base station (ie each radio head) to prepare to perform measurements on a certain frequency and time slot. The instruction message I1 representing this command is represented in the figure by an arrow between the central unit CU and one of the radio heads. Although FIG. 1 shows only one arrow, instruction messages are sent from the central unit to all radio heads. Of course, instruction I1 is preferably limited to certain radio heads for which measurements may only be meaningful within a certain restricted geographical area or even only for a single radio head.

- The central unit CU sends an order 12 to the mobile station MS ordering it to send a dedicated predefined message within a specific time (time slot) on a specific channel (frequency), as previously indicated to the radio head.

- Sending by the radio head BS1 an order message 13 for sending predefined messages intended for the mobile station MS, the order message 13 being transmitted to a specific mobile station MS. The central unit can send commands to multiple radio heads not to schedule any traffic for a certain time and on a certain channel. This is indicated in FIG. 1 by the arrow between the central unit CU and the radio head BS1. The reason for this is that it is desired that the predefined messages sent by the MS be heard by as many radio heads as possible in order to obtain cell relations not only to the nearest radio heads but also to further radio heads. Low C/I (carrier-to-interference ratio) and C/N (carrier-to-noise ratio) conditions on these links can complicate this. The central unit can thus also limit interference on the relevant frequency and time slot and listen to predefined messages on this channel. This "quiet request" may or may not be implemented as an optional feature. This approach can also be extended to include adjacent channels or frequencies in order to limit adjacent channel interference during measurements. For example, in a system such as packet switching GPRS, the uplink transmission is controlled by an uplink state flag (USF), and the mobile station is allowed to transmit only when the USF has a certain value. Silence requests can therefore be easily implemented in such systems by taking the approach of not setting the uplink status flag, except in the case where the mobile station is ordered to send a predefined message.

- The MS sends predefined messages on defined frequencies and time slots. This is indicated in the figure by the arrow 15 between the mobile station and the radio head BS1.

- Multiple wireless heads receive the predefined message 15. The radio head performs the measurements requested by the central unit CU (such as signal strength measurements) and sends the results to the CU. In order to establish a cell relationship, the above process is repeated until sufficient cell values are obtained. It may be desirable to perform these measurements intermittently, filter their results, and update cell relationships as the cellular system evolves. The predefined message may include the identity of the transmitting mobile station, the identity of the connected radio head, the transmit power at which the mobile station transmits the message, or any other suitable information. However, in case the central unit only orders a specific mobile station to send the predefined message, then the identity of the mobile station is already known to the system and these contents in the predefined message are redundant.

Because predefined messages should be listened to even in harsh wireless environments, low-rate coding (such as 1/2 rate or lower) should be used for protection. If decoding is still not successful, an additional identical predefined message can be sent and the two decoded messages can be soft combined together. But this process may only take place if several radio heads or a particular radio head cannot decode the predefined message sent for the first time, since this second sent command has to be issued by the central unit. It should also be noted that in another embodiment of the invention all necessary information is already available at both the mobile station and the network side, the predefined message does not have to carry any information and thus the encoding is not critical.

It is also possible to send predefined messages with idle MSs, but running MSs can also be used. In such cases, it may be necessary to restrict what information is included in the predefined messages. If the above-mentioned "quiet request" is not sent from the central unit (CU), the above-mentioned method of cell relation measurement is suitable to be performed under low traffic conditions when the number of undisturbed channels (frequencies) is large.

Referring now to FIG. 2, FIG. 2 illustrates an example of a distributed indoor system to which the present invention is applied. This type of system usually transmits signals at low power and the cells are usually small. The system is referred to herein as an indoor system, although it can of course also be a system serving in an outdoor environment. Multiple radio heads RAD (Radio Antenna Devices) provide radio coverage to cells 1-3. The coverage area of one RAD is called a sub-cell, and multiple sub-cells define a cell 1-3. Each RAD is controlled by a central control unit CU, which is responsible for several cells. The figure shows that the wireless heads covering 3 cells are all connected to the same central unit, but the number of cells can be arbitrary, just as the number of RADs serving each cell is also arbitrary. In such systems cells are usually assigned a set of frequencies, and each cell's RAD is able to transmit on all of these frequencies, although not simultaneously. The invention is well suited for use in systems where the central unit can order each RAD to perform measurements on mobile stations in a cell sending predefined messages and can obtain sub-cell relations in the same way as cell relations are measured. It should be understood that the relationship between cells is still important and that such measurements are also made in these types of systems.

Figure 3 illustrates a macrocellular system to which the present invention is applied. In a similar manner to that described above, in a system such as GSM a central unit such as an MSC (Mobile Services Switching Center) or a BSC (Base Station Controller) can instruct any terminal within the service area of any radio head connected to it to transmit Predefined messages. The MSC can also order multiple radio heads to listen to the message and report the measurement results back to the MSC. The MSC itself can store the measurement results, or it can send the results to any other node for processing and storage.

Referring now to Figure 4, it shows an exemplary path gain matrix. This is a way to store the measurements made by the radio head on predefined messages. The vertical axis corresponds to different wireless heads and the horizontal axis corresponds to the transmission source area of the predefined message. For example, the relationship between cells (represented by 2 here) and radio heads (represented by 1 here) can be stored as matrix element g12. Thus, the results of the measurements performed by the radio head serving cell 1 on the signal transmitted from cell 2 are stored at matrix element g12. Matrix elements may represent, for example, path gain distribution functions corresponding to observation sequence numbers. Of course other representations are also possible.

Figure 5 shows a flow diagram of one embodiment of the present invention. A measurement request command is sent from the central unit to the plurality of wireless heads to start the measurement procedure, 710. This command at least includes: a radio head instructs a mobile station or other type of terminal to send a predefined message, and at least one radio head listens to a specific frequency in order to receive the predefined message. A radio head then sends, 720, a transmission request to the mobile station MS according to the measurement request command. The mobile station receives the type of message to send in a send request, tunes to the correct frequency and sends the predefined message, 730. At least one radio head performs measurements on predefined messages according to measurement requests and reports these measurements to the central unit. At the central unit, these measurements are received and processed in a manner suitable for more uses.

Figure 6 shows another embodiment of the invention, with the difference that the measurement request is sent together with the silence request. The silence request instructs the radio heads to order the mobile stations they serve not to transmit on a certain frequency for a certain period of time. Interrupting a transmission on a certain frequency can be accomplished by reassigning the user to another frequency, or simply waiting until the transmission is terminated and no more calls are allocated on that designated frequency.

This silence request is of course ignored after the mobile station accepts the order to send the predefined message. In this way, interference at a certain time and on a certain frequency is cleared, and the radio head can more easily receive predefined messages sent on that time and on that frequency. Therefore, according to this technical method, the cell relationship between distant cells can be obtained, and the reliability of the relationship measured in this way is greatly improved.

In another embodiment it is possible to instruct the mobile terminal to measure a predefined message sent by the radio port and report the measurement result to the central unit. In this case, at least one radio port should be sent a command of a predefined message, and an order to listen to a certain frequency at a certain time can be sent to the mobile station through the radio port. The results measured by the mobile terminal are then sent to the central unit via the wireless head. In this embodiment, at least for battery saving reasons, the processing of the measurement results is preferably performed at the central unit.

Turning now to Figure 7, Figure 7 further describes an embodiment where measurements are made in the mobile station instead of the radio head. Shown in the figure is a wireless head BS1. ． A plurality of cells C1 served by the BSN. ． Cn and a plurality of mobile stations M1. ． Mm. As mentioned above, the central unit can send a silence request on a certain frequency and allow only one radio head (eg BS1) in a certain area to transmit on a certain frequency f1 with a certain output power. Also in this method the service interruption on a certain frequency can be realized by reallocating another frequency for the user or by simply waiting until the transmission is terminated and no more calls are allocated on the specified frequency. The central unit then commands the mobile station M1. ． Mm measures the received signal strength on frequency f1. This command can be implemented by including f1 in the MAHO list (Mobile Assisted Handover). The MAHO list is a list of frequencies where the mobile station performs routine measurements, according to which it can switch to a high-quality frequency once the signal quality on the current frequency deteriorates. This list can also be used to force the mobile station to measure cell relations on a certain frequency. These features of the present invention will also be described below.

Then the mobile station M1 located in different cells. ． Mm reports the signal strength measured on frequency f1 to the central unit, where the central unit calculates the cells C1 and M1 served by BS1. ． Path gain between cells occupied by Mm. After collecting enough measurements of cell C1 when BS1 transmits on frequency f1, BS1 can be ordered to be silent on f1 and another base station (eg BS3) to transmit on f1, and in the same way cells C3 and For M1. ． Relationship between cells served by Mm.

A particular base station should transmit long enough for the mobile to get good measurements. Repeated measurements over some very short time interval are of limited usefulness because business conditions will vary very little. Thus, it is convenient to use f1 to measure the relationship of some other cells, for example from BS3, after a period of time. By repeating this strategy, allowing different BSs to transmit on f1 while others are silent on f1, it is possible to obtain a wide range of cell relationships in an efficient manner. Of course several frequencies like f1 can also be used. This may be a tradeoff for the total amount of resources used for traffic that can be blocked under different circumstances.

As mentioned earlier, it may be important not only to measure signal strength but also to calculate path gains between different cells. Another quality measure that is notable eg for frequency planning purposes is C/I (ie Carrier to Interference Ratio). The present invention can be easily modified to calculate C/I values rather than just path gain values. For example, in the embodiment described above, the mobile station M1. ． Mm collect and report signal strength measurements not only from frequency fl, but also from their traffic themselves within the serving cell, eg M4 measures signal strength on f4. The signal strength on f1 corresponds to I from a certain cell and the signal strength on f4 corresponds to C at a certain location and time, giving C/I immediately. Note that C/I can be calculated in this case if M4 in C4 receives on frequency f1 which is interfered with by the transmission from BS1 in cell C1.

As will be described in more detail below: it is even possible to estimate the uplink C/I using the above measurements from the same downlink. In addition to the above, the radio head only needs to collect signal measurements from mobile stations within the cell it serves. The path gain from BS1 to M4 in the mobile station (for example, C4) can be known. Since the output power of the base station is known, it is possible to estimate the uplink interference to cell C1 caused by M4 in cell C4. The desired uplink interference distribution from the mobile stations in C4 to the C1 uplink can be obtained by repeated measurements. At the same time, measurements of the C1 uplink from the mobile stations in C1 may be collected. For the uplink, interference and its own signal strength are approximately independent of each other, and we can estimate the uplink C/I distribution of cell C1 by convolving C and I distributions. This approximation for the downlink is not possible because the downlinks C and I are correlated.

It should be noted that there are many embodiments in which the present invention may be conveniently practiced. For example the invention can be used to obtain short-term information about current interference conditions. When an idle MS wants to start sending, it may need to know how this will affect the rest of the network. The present invention thus provides means for sending a "test" burst from the MS in order to determine how much interference will occur if the MS starts to transmit. This is also useful during handoffs.

Another advantage of the invention is that, if the measurements are performed frequently, it is possible to obtain a "Snapshot path gain matrix" describing the instantaneous path gain values between all MSs and BSs (radio heads). This matrix is useful for algorithms such as Fast ACA (Adaptive Channel Allocation). The path gain matrix estimate can be updated at regular intervals by having all MSs send uplink messages while the rest of the users wait. This "fast" approach is particularly well suited for packet-switched communications where traffic delays are often allowed. It is also possible to reserve a dedicated channel in the system for this purpose.

It can be understood that, in the foregoing implementation, the received signal measurement results are used to determine the attenuation cell relationship according to the amplification value. But sometimes it is necessary to express the cell relationship with the carrier-to-interference ratio (C/I). Of course, other cell relationship measures can be calculated by using the amplification value. According to an aspect of the invention, downlink cell relationships are expressed in terms of C/I ratios using amplification values obtained from uplink signal strength measurements rather than actual downlink signal strength measurements. Since the frequency spread of the uplink and downlink spectrum is relatively narrow, it is assumed that the uplink amplification value also corresponds to the uplink amplification value. In short, the amplification value obtained in the uplink direction also represents the amplification value in the downlink direction. Under this assumption, the downlink cell relationship is estimated in the form of C/I ratio based on the uplink amplification value and the known power output of the base station. The base station can then measure the signal strength C of the communication traffic. The signal strength C can be combined with the transmission interference of surrounding cells to obtain the carrier-to-interference ratio (C/I). This C/I ratio can be stored in the matrix instead of or along with the amplification value. Thus, for all cell pairs, the invention provides the distribution of the uplink or downlink C/I conditions of one of the cells given that the other cell uses the same frequency, and the C/I distribution under the opposite condition.

Downlink I can be estimated by multiplying the known base station power output by the corresponding uplink amplification value. The downlink C can be estimated by multiplying the known base station power output in the cell by the corresponding uplink amplification value. Alternatively, downlink C may be a signal strength measurement reported by the mobile station. It should also be noted that due to the correlation of C and I in the downlink, simultaneous measurements of C and I are necessary to obtain the correct downlink distribution. But for the uplink, the C and I distributions can eg be collected separately and then convolved. This is because the distribution of uplink carrier strength and interference is uncorrelated. Transforming the collected information about co-channel C/I into information about adjacent channel C/I can be easily accomplished by reducing the interference by an appropriate factor.

Expansion of cellular telephone networks often results in the gradual establishment of new cells through the installation of new base stations. It is therefore necessary to estimate the relationship of the new cell to the existing cells before making the new cell operational. Of course the above method can be modified to handle this situation. The most critical point is to determine which mobile stations are in the "virtual" cell (ie, the new cell that is not activated), if the cell is operational. Once these mobile stations are identified, the base station in the actual cell can measure the signal strength of the random access bursts associated with these mobile stations. The signal strength measurements can then be used to calculate the attenuation or C/I distribution, which can then be considered to belong to the virtual cell.

To determine which mobile station will belong to the virtual cell once activated, we can use mobility assisted handover (MAHO) measurements, which are performed by the base station. An antenna located at the location of the virtual base station transmits on a frequency included in the MAHO list of all mobile stations in the area and then reports the MAHO measurements to the central unit. Although no mobile station is actually connected to the virtual base station, the central unit can determine which mobile station will be connected to the virtual cell, if it is activated, simply by considering standard cell selection criteria. It should of course be noted that mobile stations currently located in areas not covered by existing cells will not be used in the measurement process.

It is of course possible to perform measurements from mobile stations located in other cells together with a device possibly located at the base station location (eg a virtual base station). If we are interested in the C/I relationship, C can be estimated using MAHO measurements or signal strength measurements and possibly decoding by a virtual base station. By transmitting signals from the virtual cell station, the virtual base stations that are to be measured in other cells may cause interference. Conversely, the virtual base station can measure the interference generated by other cells. However, interference from other cells must be distinguished from the carrier signal that would be generated if the mobile station were connected to a virtual base station. Carrier signal strength (C) and interference (I) can be distinguished from the timing of the reported MAHO measurements as described above.

Similarly, mobile stations that will belong to a virtual cell can be used to generate or measure interference. Based on the knowledge of which mobile station will belong to the virtual cell, we can measure interference at other cell base stations. The carrier signal strength from the mobile station that will belong to the virtual base station can also be measured by a receiver included in the virtual base station. Assuming that the uplink and downlink amplification values are the same, the carrier signal strength of the mobile station belonging to the virtual base station can be obtained according to the uplink amplification value and the transmission power output of the virtual base station. The thus obtained carrier signal strength and the interference measured at the mobile station are time-correlated in the CU. In addition, the carrier signal strength from the virtual base station at the mobile station that will belong to the virtual cell can be measured using MAHO measurements by including a list of frequencies used by the virtual base station to communicate in the virtual cell.

It is therefore to be understood that the foregoing is a description of embodiments of the present invention and that modifications may be made without departing from the spirit and scope of the invention as defined by the following claims.

Claims (37)

1. method of in cellular communication system, determining the cell relations between a plurality of sub-districts, each sub-district provides service by at least one no the end of a thread, and the method comprising the steps of:

-on time of determining and the frequency determined, send predefine message from transmitter;

-at least one receiver receives predefine message on described definite frequency;

-at least one receiver is measured the received signal intensity of described predefine message;

-identification sends the transmitter of predefine message at least one receiver;

-report the received signal intensity of described measurement to central location;

-generation cell relations value in central location, the path gain of the described predefine message of this value representation from described transmitter to described at least one receiver.

2. the process of claim 1 wherein that the output power signal of the predefine message that sends from transmitter is pre-determined by central location.

3. the process of claim 1 wherein that the output power signal of the predefine message that sends from transmitter is reported to central location.

4. the process of claim 1 wherein that transmitter is a travelling carriage.

5. the process of claim 1 wherein that at least one receiver is no the end of a thread.

6. the method for claim 5, wherein this no the end of a thread is not no the end of a thread of the sub-district service that is positioned for transmitter.

7. the process of claim 1 wherein that the transmission of predefine message is started by the order that comes from central location.

8. the method for claim 1 also is included in the step that sends before the predefine messages step:

-sending quiet request from the central location of system, wherein said quiet request is an order that does not allow other transmitting element send on described definite time and described definite frequency.

9. the process of claim 1 wherein that described predefine message is the message through coding.

10. the method for claim 7, wherein bit rate is equal to or less than 1/2.

11. a method of determining instantaneous interfere information between a plurality of sub-districts in cellular communication system, each sub-district provides service by at least one no the end of a thread, and the method comprising the steps of:

-send predefine message from travelling carriage in the time of determining and definite frequency;

-a plurality of no the end of a thread receive predefine message on described definite frequency;

-received signal the intensity of the described predefine message of measurement in no the end of a thread;

-identification sends the transmitter of predefine message in no the end of a thread;

-estimate by described predefine message that at each no the end of a thread Serving cell at the interference value of introducing in the ongoing connection, wherein said definite frequency is used for communication on described definite frequency.

12. a method of determining the cell relations between a plurality of sub-districts in cellular communication system, each sub-district provides service by at least one no the end of a thread, and the method comprising the steps of:

-send measuring command from central location at least one wireless hair;

-send order at least one base station;

-at least one travelling carriage sends predefine message on Traffic Channel, the message of wherein said transmission is determined by described transmission order;

-receive described predefine message and carry out measurement at least one no the end of a thread according to described measuring command;

-report described measurement result to central location.

13. the method for claim 12 also comprises step:

-during measuring, remove Traffic Channel to disturb.

14. the method for claim 12, wherein measuring command comprise at least Measuring Time section, Traffic Channel and predefine message one of them.

15. the method for claim 12 wherein sends order by a no the end of a thread at least one travelling carriage at least.

16. the method for claim 12, wherein send a command to comprise less transmitting time section, Traffic Channel and predefine message one of them.

17. the method for claim 12, the step of wherein measuring described predefine message comprise determine at least signal strength signal intensity, signal identification, time delay expansion and signal-to-jamming ratio one of them.

18. a method of determining the cell relations between a plurality of sub-districts in cellular communication system, each sub-district provides service by at least one no the end of a thread, and the method comprising the steps of:

-transmitter sends predefine message on time of determining and the frequency determined;

-at least one receiver is received in the described predefine message on the described definite frequency;

-this at least one receiver is measured the signal strength signal intensity of the described predefine message that is received;

-at least one receiver is identified in the no the end of a thread that when sending predefine message dispatching station is provided service;

-to the described received signal intensity that records of central location report;

-produce path gain value, the path gain of the described predefine message of this value representation at central location from described transmitter to described receiver.

19. a cellular communication system comprises:

-a plurality of sub-districts wherein provide wireless coverage to each sub-district by at least one no the end of a thread;

-one central location that is connected with a plurality of no the end of a thread;

-from described central location to the lose one's life device of order of a plurality of wireless hairs that are attached thereto, comprise the order that the no the end of a thread of at least one indication is measured in the wherein said order on time of determining and definite frequency;

-be sent in definite time and the frequency determined sends the device of the order of predefine message from described central location to travelling carriage;

-measure the device of the received signal intensity of at least one above-mentioned predefine message at a plurality of no the end of a thread;

-in described central location, be stored in the device of the expression of the measurement result that a plurality of no the end of a thread finish.

20. a method of determining the cell relations between a plurality of sub-districts in cellular communication system, each sub-district provides service by at least one no the end of a thread, and the method comprising the steps of:

-send predefine message from least one no the end of a thread of serving the first definite sub-district in time of determining and the frequency determined, wherein carrying out described transmission and described central location order by the central location order is that the no the end of a thread of other sub-district service in the appointed area interrupts transmission on described assigned frequency;

-on described definite frequency, receive predefine message at least one travelling carriage, wherein this at least one travelling carriage is positioned at described appointed area and described definite different sub-district, first sub-district;

-on described assigned frequency, measure the received signal intensity of described predefine message at least one travelling carriage;

-to the described received signal intensity that records of central location report;

-the cell relations that produces in central location between the sub-district that this first sub-district of determining and described at least one travelling carriage be positioned is estimated, and wherein said cell relations is estimated at least in part the signal strength measurement based on described report.

21. the method for claim 20, wherein said transmission interruption on described assigned frequency are to realize by redistribute other frequency that is different from described assigned frequency to the user.

22. the method for claim 20 also comprises step:

-provide the received signal intensity of the signal that the wireless hair of service send from the sub-district that is positioned at least one travelling carriage wherein at least one moving table measuring, and report these measurement results to central location.

23. the method for claim 20, wherein the transmission of the described predefine message on a definite frequency stops from least one no the end of a thread that service is provided for the described first definite sub-district, and the transmission of the second predefine message is from providing at least one no the end of a thread startup of service for second sub-district of determining on described definite frequency, second sub-district that should determine be different from described first sub-district of determining, and to repeatedly measuring, report and produce the step that cell relations is estimated from the transmission of described definite second sub-district.

24. the method for claim 22, wherein the cell relations that produces at central location is estimated the described signal strength measurement of sending here based on the wireless hair that service is provided from the sub-district that is positioned at least one travelling carriage at least in part of reporting.

25. the method for claim 20, wherein said travelling carriage are intercepted the indication of described assigned frequency and are illustrated in MAHO frequency inventory.

26. the method for claim 22, the signal that wherein provides the wireless hair of service to send from the sub-district that is positioned at least one travelling carriage sends in the frequency different with described assigned frequency.

27. the method for claim 24, wherein cell relations is estimated channel disturbance and is compared C/I.

28. the method for claim 23 wherein is that all possible sub-district is to collecting described cell relations measurement result and placing it in the cell relations matrix in the appointed area.

29. the method for claim 20, wherein said predefine message is not carried any information.

30. a cellular communication system comprises:

-a plurality of sub-districts wherein provide wireless coverage by at least one no the end of a thread to each sub-district;

-one central location that is connected with a plurality of no the end of a thread;

-be used for from described central location to the lose one's life device of order of a plurality of wireless hairs that are attached thereto, comprise the order of the no the end of a thread of at least one indication transmission predefine message on time of determining and the frequency determined in the wherein said order;

-be used for sending one in the time of determining with the frequency determined is measured and to the device of central location report signal intensity order to travelling carriage from described central location;

-be used for the device of the expression of the measurement result carried out at a plurality of travelling carriages at least in the storage of described central location.

31. a travelling carriage that is connected with cellular system comprises:

-be used on assigned frequency, receiving the device that measure signal intensity is indicated from central location in the time of determining;

-be used for the device that receives the measure signal intensity indication from central location in the time of determining being different from the frequency of described assigned frequency;

-be used on described assigned frequency device in the time measurement signal intensity of determining;

-being used to measure from the signal strength signal intensity of the signal that the wireless hair of service send is provided for sub-district, described travelling carriage place, wherein said signal sends being different from the frequency of described assigned frequency.

-be used for the device that described cell relations measurement result is estimated and reported to described central location to calculation plot relation.

32. in the communication system that can be divided into a plurality of sub-districts, determine the method for cell relations, comprise step:

-comprise an inventory of distributing to the wireless frequency of void cell at least to the transmission of the travelling carriage in a plurality of sub-districts;

-measure signal intensity at least one wireless frequency channel;

-signal strength measurement at least one wireless frequency channel is handled, so that determine the relation of each sub-district in void cell and a plurality of sub-district.

33. the method for claim 32 is wherein carried out signal strength measurement at void cell.

34. the method for claim 32 is wherein carried out signal strength measurement at travelling carriage.

35. the method for claim 32, wherein travelling carriage sends signal at least one wireless frequency channel.

36. the method for claim 32, wherein travelling carriage received signal at least one wireless frequency channel.

37. the method for claim 32, wherein travelling carriage is carried out MAHO (MAHO), and wherein uses the MAHO-inventory to send inventory to travelling carriage.

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