JP2000315975A - Mobile station equipment - Google Patents

Abstract

(57) [Problem] To provide a mobile station device of a cellular telephone system in which a plurality of base stations share a carrier frequency, and to enable a monitor display of the line quality of a currently linked base station. SOLUTION: A receiving section receives a CDMA spectrum spread radio signal, and a spectrum despreading of a radio signal from a base station linked by a demodulation section 4 to separate a pilot channel from a paging channel or a traffic channel. I do. During the reception period in the standby reception state, the measurement unit 10 measures the signal-to-noise ratio between the pilot channel and the paging channel, and the conversion unit 11
The line quality is evaluated based on these signal-to-noise ratios.
The one with the lower evaluation is displayed on the display unit 12 as the line quality. In a call state, the measurement unit 10 and the conversion unit 11 are controlled by a pilot channel and a traffic channel (TCH).
Perform the same evaluation, and the display unit 12 displays the line quality.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile station apparatus for wireless communication, and more particularly to a CDMA (Code Division Mud).
The present invention relates to a mobile station apparatus suitable for use in a digital cellular telephone system of the ltiple access (code division multiplex) system.

[0002]

2. Description of the Related Art In a typical CDMA digital cellular telephone system, a downlink signal received from a base station from a base station is multiplexed by code-multiplexing information signals of a plurality of users and a control signal of a radio channel. Before being transmitted as a radio signal, the multiplexed signal is subjected to a spread spectrum process using a pseudo-noise sequence (spreading code) assigned to the base station.

Therefore, the mobile station apparatus demodulates a multiplexed signal by spectrum despreading using a replica of the pseudo noise sequence of the base station prepared on the receiving side.
In order to separate the control signal and the information signal assigned to the own station device from the multiplex signal, it is necessary to perform a despreading process using a multiplex code.

In such a system, as a control signal, a pilot signal for synchronizing the phase of a pseudo-noise sequence which is a replica of the base station with the phase of the pseudo-noise sequence of the base station, or the mobile station is called upon arrival of a call. Paging signals, signals for transmitting other system information, and the like are multiplexed.

In particular, a pilot signal is multiplexed with a unique known code, and the mobile station apparatus demodulates the pilot signal to acquire the phase of a pseudo-noise sequence code of a replica, and maintains synchronization. The received paging signal and information signal are inversely assigned by using a replica pseudo-noise sequence code whose timing is synchronized with the pseudo-noise sequence code of the base station assigned and notified by the base station. The spread spectrum processing is performed. Therefore, the error rates of the demodulated information signal and control signal are greatly affected by the signal-to-noise ratio of each of these signals and the signal-to-noise ratio of the pilot signal used for synchronizing the replica pseudo-noise sequence code.

[0006] Here, the noise sources include, in addition to the circuit noise, downlink signals transmitted from a base station outside the cell or sector where the mobile station device is located, and information allocated to the own station. Signal. This is because these signals are transmitted using a common frequency. The separation and identification of various signals are performed by the phase of the spread spectrum code and the multiplex code.

[0007] Conventional cellular telephone systems based on the CDMA system include the FDMA (frequency division multiplex) system and the TDMA (time division multiplex) system. In these systems, a graphic display based on a received electric field strength has been conventionally provided as a monitor of the quality of a wireless line for a user. For example, Japanese Patent Application Laid-Open No. 7-2185
Japanese Patent Application Publication No. 62-62103 describes a technique in which an AGC section for automatically controlling the level of a received signal is provided, and received field strength information is obtained from a gain control signal of the AGC section and displayed.

FIG. 5 is a block diagram showing such a conventional mobile station apparatus, wherein 50 is an antenna, 51 is a receiving section, and 52 is a receiving section.
Is an AGC section, 53 is an amplification section, 54 is a demodulation section, 55 is an audio section, 56 is an A / D conversion section, 57 is a control section, and 58 is an LCD.
(Display) section.

In FIG. 1, an antenna 50 and a receiving unit 51 are provided.
The level of the radio signal received by the AGC section 51 is automatically controlled by the AGC section 51, further amplified by the amplification section 53, and supplied to the demodulation section 54 as an IF (intermediate frequency) signal. The demodulation section 54 demodulates the IF signal into reception data, and the audio section 55 synthesizes and outputs a voice from the reception data. An RSSI (electric field strength signal) obtained by voltage-converting the gain control signal of the AGC unit 52 is converted into an A / D converter 56
After that, it is supplied to the control unit 57 together with the line control information of the received data. The control unit 57 generates graphic display data based on the supplied RSSI and supplies it to the LCD unit 58. As a result, the LCD unit 58 performs the graphic display a according to the data.

Here, the graphic display a indicates the electric field intensity by the number of bars to be displayed. Generally, the display is such that the number of bars increases as the electric field intensity increases and the number of bars decreases as the electric field intensity decreases. Done. With this display, the user can visually check the quality of the provided wireless line. This is because, in the case of the FDMA system or the TDMA system, the carrier frequency of the radio signal received by the reception unit 51 individually corresponds to the information signal and control signal provided for each user, and the electric field strength of the received radio signal is This is because it is directly reflected in the signal-to-noise ratio of an information signal or the like.

[0011]

In the CDMA system, as described above, one carrier frequency is shared by a plurality of base stations and sectors. In the case of the prior art shown in FIG.
The RSSI obtained from the unit 52 includes the influence of a downlink signal from a base station other than the currently linked base station. For example, if the electric field strength of the other base station serving as an interference source is sufficiently strong and the signal strength of the base station currently linked to the mobile station apparatus is weak, the error rate of the radio link during the period when this link is maintained Even if is deteriorated, the display based on the RSSI in the above-described conventional technique indicates a strong electric field state. In other words, the RSSI may be affected by the electric field strength of a signal from another base station other than the linked base station, and thus always provides the user with quality information of the radio line used. There was a problem that it was not.

An object of the present invention is to solve such a problem, prevent the influence of the electric field strength of a signal from a base station other than the linked base station, and reduce the radio signal from the linked base station. It is an object of the present invention to provide a mobile station device capable of providing a user with accurate information on a radio wave state at the time of receiving a mobile station.

[0013]

In order to achieve the above object, the present invention provides a multiplexed signal obtained by code division of one or a plurality of speech information signals and a control signal of a radio channel by performing a spread spectrum process using a spread code. A mobile station apparatus for receiving a radio signal from a base station, demodulating the received radio signal into a multiplexed signal assigned to the mobile station by spectrum despreading, and demodulating the multiplexed signal. Demodulation means for despreading and separating and outputting the call information signal allocated to the own station and the control signal in accordance with the state of the own station with respective codes used for multiplexing, and demodulation and separation by the demodulation means Evaluating means for evaluating the quality of the radio line for each of the performed call information signal and the control signal, and displaying a state of a radio wave based on the evaluation result; Spreading code is different for each base station for, the demodulation means is the structure where the spectrum despread radio signal received by using a spreading code linked the base station is synchronized to the spreading code used.

With this configuration, the radio wave condition of a radio signal from a base station linked to the own station can be detected, and accurate quality evaluation of a radio line can be performed.

Further, according to the present invention, when in the standby reception state, the quality information of the lower evaluation of the radio line quality information obtained from the signal-to-noise ratio of the pilot signal and the paging signal included in the control signal is lower. And in the call state, the quality information of the radio channel obtained from the pilot signal of the control signal and the signal-to-noise ratio of the information signal assigned to the own station. Out of the evaluation, the quality information with the lower evaluation is the target of the evaluation.In both the standby reception state and the call state, the radio wave condition of the radio signal from the base station linked to the own station is always maintained. Is detected, and an accurate quality evaluation of a wireless line can be performed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a radio signal received by a mobile station apparatus according to the present invention will be described using a transmitter of a base station of a typical CDMA digital cellular portable telephone system shown in FIG. Here, a paging channel (PaCH) for calling that is important in the standby reception state is focused on.

In FIG. 2, first, a paging message including information such as information for simultaneously reading out all mobile stations in a zone and a telephone number for calling a predetermined mobile station device is exclusive as a data string. OR gate 2
0 is supplied. The output signal of the long code PN (Pseudo Noise) code generator 22 is supplied to the exclusive OR gate 20 by the decimator 21 and the paging channel (PaC).
H) is supplied after being decimated to the symbol rate. The long code PN code from the long code PN code generator 22 has a period of (2 ⁴² -1), and its phase can be adjusted by the long code mask bits.

The output signal of the exclusive OR gate 20 is obtained by scrambling the paging message with the very long PN code sequence. In order to multiplex each symbol of the paging channel (PaCH) with a signal of another channel having a different function, the exclusive OR gate 23 sets the paging channel (Walsh function 24) out of 64 kinds of orthogonal sequences as a paging channel (PaCH). PaC
By using the specific orthogonal sequence assigned to H),
The orthogonal spread is performed on one chip corresponding to this specific orthogonal sequence among the 64 chips.

The paging channel (PaCH) orthogonally spread by the exclusive OR gate 23 is supplied to a multiplexing circuit 25, and a pilot channel (PiC) which is another control signal.
H), a synchronization channel (SCH), and a traffic channel (TCH) including a speech information signal. Actually, these binary codes are replaced with pulses of both polarities of 1 and −1, and gains are multiplied based on the power distribution of each channel and added. Where the pilot channel (PiCH)
Uses a specific code sequence predetermined for this cellular telephone system among the 64 Walsh functions,
It is orthogonally spread to one chip corresponding to this unique orthogonal sequence out of 64 chips. Therefore, this pilot channel (PiCH) is
(PaCH) and orthogonal to other channels.

In the multiplexed signal output from the multiplexing circuit 25, packets are formed by a paging channel (PaCH) and a traffic channel (TCH), and a synchronization channel (SCH) is positioned at the head of each packet. In the traffic channel (TCH), information signals (that is, call information signals) to each mobile station apparatus during a call are serially arranged, and the arrangement order and movement of these call information signals in the traffic channel (TCH) are changed. Information indicating the correspondence with the station device is included in the paging channel (PaCH). The pilot channel (PiCH) is a continuous signal, which is mixed with such packets and multiplexed.
This pilot channel (PiCH) is orthogonal to each of the channels that make up the packets, and therefore does not interfere with the channels that make up these packets.

The packet having such a configuration is mixed with a pilot channel (PiCH) to form a repetition multiplexing circuit 25.
Output from The paging channel (PaCH) in this packet has information of a general call for confirming the presence of the mobile station device in the zone assigned to the base station, and all mobile stations located in this zone Upon receiving this, the station device responds to notify the base station that it is located in this zone. Thereby, the base station can grasp all the mobile station devices existing in this zone. Also, when the base station calls the desired mobile station device, the paging channel
Information such as a telephone number designating this mobile station device is added to (PaCH). Further, when the desired mobile station device is linked to the base station by off-hook for the call, a traffic channel (TC
A call information signal to be transmitted to the mobile station device is added to H), and at the same time, information indicating the position of the call information in the traffic channel (TCH) is added to the paging channel (PaCH).

The multiplexed signal obtained from the multiplexing circuit 25 in this manner is branched into two as I and Q signals and supplied to multipliers 26 and 27, respectively. In the multiplier 26, I
An I-channel pilot PN code is supplied from a channel pilot PN code generator 28 and multiplied by the I signal.
A Q channel pilot PN code having a phase different from that of the I channel pilot PN code is supplied from the N code generator 29 and multiplied by the Q signal. Therefore, the I and Q signals of the two-phase modulation are spread to the four-phase modulation signal by the pilot PN codes of these different sequences. Additional I used in this four-phase diffusion, Q-channel pilot PN code is a code sequence of 2 ¹⁵ cycles called short code. Spread spectrum is performed by these code sequences. These I and Q channel pilot PN codes are:
This is a spread code for performing a spread spectrum process.

The I and Q four-phase spread signals obtained as described above are band-limited by baseband filters 30 and 31, respectively, and then subjected to local carrier modulation by a quadrature modulator 32 to be synthesized as radio signals. Sent.

The operation of the base station has been described above.
In the case of the digital cellular mobile phone system of the system, it is possible to prevent mutual interference in the area where the other zones overlap by making the phase of the short code different from that of the base station in the other zone by giving an offset. As a result, the carrier frequency is shared between the base stations.

The present invention is for receiving a radio signal transmitted from a transmitting station as described above, and an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a mobile station apparatus according to the present invention, in which 1 is a transmitting / receiving shared antenna,
2 is a duplexer, 3 is a receiver, 4 is a demodulator, 5 is a controller, 6
Is a voice section, 7 is a receiver, 8 is a transmitter, 9 is a transmitter, 10
Denotes a measurement unit, 11 denotes a conversion unit, 12 denotes a display unit, and 13 denotes an operation unit.

Referring to FIG. 1, this embodiment uses a multiplexed transmission / reception antenna 1, a duplexer 2, a reception unit 3 for receiving a radio signal, and a baseband band reception signal output from the reception unit 3. A demodulation unit 4 for demodulating the signal, a measurement unit 13 for measuring the signal-to-noise ratio of the demodulated multiplexed information signal and the control signal, and a signal for the signal-to-noise ratio output from the measurement unit 13 Conversion unit 11 for converting into quality information
A display unit 15 for displaying quality information output from the conversion unit 11 and other information provided to the user; a paging channel (PaCH) and a synchronization channel (SCH) which are control signals output from the demodulation unit 4 , A control unit 5 for controlling each unit of the embodiment, a signal of a traffic channel (TCH) as an information signal output from the control unit 5, processed and output to a receiver 7, and a transmitter An audio unit 6 that processes an audio signal from the control unit 8 and supplies the control unit 5 with the operation signal, an operation unit 13 that supplies an operation signal corresponding to a user operation to the control unit 5,
An audio signal input from the transmitter 8 and processed by the audio unit 6 is supplied to the control unit 5 and formed by a transmission traffic channel (TCH) formed by the transmission unit and a line control signal generated by the control unit 5. It comprises a transmission unit 9 for transmitting signals. Here, the measurement unit 10, the conversion unit 11, and the display unit 12 form an evaluation unit. In FIG. 1, a signal path for operation control of each unit from the control unit 5 is omitted.

Next, the operation of this embodiment will be described.

The radio signal received from the base station via the transmission / reception shared antenna 1 and the duplexer 2 is orthogonalized to I and Q signals in a baseband band by a receiving unit 3 using a local carrier frequency. The signal is detected and supplied to the demodulation unit 4.

The demodulation unit 4 includes code generation means (not shown) for generating replicas of the short codes generated by the I-channel pilot PN code generator 28 and the Q-channel pilot PN code generator 29 of the transmitting station shown in FIG. ), The phases of the short codes generated by these code generation means are synchronized with the short codes of the base station linked to the own station, and the spectrum despreading process of the I and Q signals is performed by these synchronized short codes. Do. Then, the demodulation unit 4 further processes the I, Q
The multiplexed signal is reproduced by synthesizing the signals, the traffic channel (TCH) is separated from the multiplexed signal based on the timing of the synchronization channel (SCH), and the paging channel (PaCH) and the pilot channel (PiCH) are respectively separated. By using the code sequence of the assigned Walsh function, data (paging message) of the paging channel (PaCH) and pilot channel (PiCH)
Are separated by inverse orthogonal spreading.

The demodulated synchronization channel (SCH), traffic channel (TCH) and paging channel (PaC)
H) is supplied on the one hand to the control unit 5 and, on the other hand, together with the demodulated pilot channel (PiCH) to the measuring unit 10 of the evaluation means.

The control unit 5 determines whether the supplied data of the paging channel (PaCH) is data of a general call or data specifying a local station such as a telephone number. Is transmitted as a transmission signal from the transmission / reception shared antenna 1 to the base station via the transmission unit 9 and the duplexer 2. When the above data specifies the own station, the voice unit 6 is controlled to notify the user of the incoming call. Further, when a call is made off-hook, the call information signal of the own station in the traffic channel (TCH) is separated based on the data of the paging channel (PaCH), and the signal is transmitted to the audio unit 6 to thereby make the receiver In step 7, information from the other party can be heard by voice.
Also, the voice from the transmitter is processed by the voice unit 6,
The signal is transmitted by the control unit 5 and transmitted from the transmission / reception antenna 1 to the base station via the transmission unit 9 and the duplexer 2.

The demodulation unit 4 synchronizes the short code for performing the spectrum despreading process on the received signal with the spread spectrum with the short code at the linked base station by using a pilot channel ( PiCH) is used. This pilot channel (PiC
H) is orthogonally spread by the base station (FIG. 2) at the base station (FIG. 2) with a code sequence predetermined for the cellular telephone system among the 64 Walsh functions. Is reproduced by performing spectrum despreading with a short code that is phase-synchronized with the short code. For this purpose, it is necessary to synchronize the phase of the short code in the demodulator 4 with the phase of the sheet code of the base station.
When the phase of the short code multiplied by the short code is changed, the amplitude value of the pilot channel (PiCH) subjected to the spectrum despreading process changes with the change of the phase by the multiplication. When synchronized with the phase of the code, the amplitude value of the pilot channel (PiCH) subjected to the spectrum despreading processing becomes the peak value.

In this embodiment, this is utilized. In the demodulation section 4, the phase of the short code to be multiplied by the received multiplexed signal is sequentially changed, and the short code is separated from the multiplexed signal which is the multiplied output. Pilot channel
The optimum phase of the short code having the peak value of (PiCH) is searched for, and the phase of the short code is held at the optimum phase by timing tracking loop means (not shown).

In this manner, the spectrum-spread received multiplexed signal is subjected to spectrum despreading.

In the cellular telephone system, a base station in each zone makes a paging call to a mobile station device in the corresponding zone, and the base station compares the radio field strength of the response to the paging, and obtains the highest radio field strength. The base station that has received the response registers the mobile station apparatus assuming that the mobile station apparatus is located in the zone corresponding thereto. In this way, each mobile station device links with the base station in the zone in which it is located.

In this embodiment, when a link is made to a certain base station as described above, the demodulation unit operates such that the pilot channel (PiCH) from this base station has the optimum phase as described above. 4, the phase of the short code is set and held. In the state where the phase of the short code is set and held at the optimum phase as described above, when a radio signal from another base station other than the linked base station is mixed, the short code generated by the demodulation unit 4 is However, the phase is not optimal with respect to the pilot channel (PiCH) of the radio signal from the other base station. Therefore, the radio signal from the other base station is subjected to the spectrum despreading process using the short code. Then, it will be sufficiently attenuated. Therefore, when a link is made to a certain base station, even if a radio signal from another base station is mixed, or if the mixed radio signal is in a sufficiently strong electric field state, it is sufficiently attenuated by the demodulation unit 4. Thus, only the pilot channel (PiCH), the traffic channel (TCH), and the paging channel (PaCH) of the radio signal from the almost linked base station can be obtained.

The error rate of the multiplexed signal demodulated by the demodulation unit 4 such as the paging channel (PaCH) and the traffic channel (TCH) is determined by the synchronization of the short code in the demodulation unit 4 with the short code on the base station side. The accuracy is affected by the signal-to-noise ratio of the pilot channel (PiCH) which is involved in the accuracy, and of course, the signal-to-noise ratio of the paging channel (PaCH) and the traffic channel (TCH) itself.

Therefore, in this embodiment, the evaluation means determines the quality of the radio channel and displays the determination result on the display unit 12 to notify the user. (PiCH) and a signal-to-noise ratio of a traffic channel (TCH) and a paging channel (PaCH) allocated to the own station.

That is, a pilot channel (PiCH) demodulated and output by the demodulation unit 4 and a traffic channel (TCH) or a paging channel (PCH) assigned to the own station.
aCH) is a multi-level signal having amplitude information,
It is supplied to the measuring unit 10. In the measuring unit 10, for example, a signal-to-noise ratio obtained by measuring an amplitude average value and a variance value of each demodulated output, or further, amplitude information of a received signal before spectrum despreading supplied from the demodulating unit 4. (I, Q
An index for evaluating the energy of each demodulated output, such as a ratio with respect to an envelope, is measured.
Feed to 1.

In general, a mobile station apparatus has a standby reception state for waiting for an incoming call from a base station and a call state by calling its own station. The standby reception state is intended to reduce power consumption. Intermittent reception is performed in which a reception period and a pause period for suspending the reception operation are alternately repeated. These states are controlled by the control unit 5 according to the received information and the on / off hook.

That is, when in the standby reception state,
The control unit 5 determines whether or not the own station is designated by the paging channel (PaCH) received in the reception period and demodulated by the demodulation unit 4, and sets the next reception period when the own station is not designated. The standby reception state is continued by setting a pause period until the station is designated, and when the own station is designated, the voice section 6 is controlled to notify the user of the incoming call. On the other hand, if there is off-hook,
The control unit 5 puts each unit into an operating state and shifts to a talking state. Further, when there is an on-hook in the call state, the control unit 5 detects this and shifts to the standby reception state.

In the reception period in the standby reception state, the demodulator 4 outputs the synchronization channel (SCH) and the paging channel.
(PaCH) and a pilot channel (PiCH) are demodulated and output, and in a call state, a synchronous channel (SCH)
And traffic channel (TCH) and pilot channel
(PiCH) is demodulated and output. Therefore, the measuring unit 10 of the evaluation means indicates in the reception period of the standby reception state that
A paging channel (PaCH) and a pilot channel (PiCH) are supplied from the demodulator 4, and in a call state, a traffic channel (TCH) and a pilot channel (PiCH) are provided.
Are supplied. During the idle period in the standby reception state, the measuring unit 10 and the converting unit 11 also stop operating.

In this standby reception state, during the reception period, the measuring unit 10 demodulates the pilot channel (PiCH) and paging channel (PaCH) demodulated for each symbol by the demodulation unit 4.
And the signal to noise ratio is updated for each symbol. When in a call state, the measuring unit 10
The pilot channel (PiCH) and the traffic channel (TCH) demodulated by the demodulation unit 4 are measured. In this case, the pilot channel (PiCH) and the traffic channel (TCH) are measured every predetermined measurement period τ. Measure and update the signal-to-noise ratio.

In the conversion section 11, the pilot channel (PiC
H), a paging channel (PaCH), and a traffic channel (TCH), a reference value is set according to a gain distribution when these channels are multiplexed in the base station. For each signal-to-noise ratio, the amount of deviation from the corresponding reference value is determined, and the quality of the radio channel is determined based on the amount of deviation. The pass / fail determination method based on the signal-to-noise ratio may be, for example, a three- to five-step evaluation, assuming the number of bars in the graphic display. The association between the shift amount and the evaluation value can be performed by providing a reference table for each demodulated output and using this reference table.

FIG. 3 is a flowchart showing the operation of the conversion unit 11 by the control unit 5 during the reception period in the standby reception state.

In the figure, the paging channel of the own station is shown.
The conversion unit 11 is activated every time the (PaCH) reception period ends (step 100). At this time, the signal-to-noise ratio between the pilot channel (PiCH) and the paging channel (PaCH) is measured and output by the measurement unit 10, and the conversion unit 11
Obtains these signal-to-noise ratios (step 10).
1) The quality evaluation value of the radio channel for the pilot channel (PiCH) and paging channel (PaCH) is obtained from each of the above reference tables having the signal-to-noise ratio as an argument (step 102). Then, these two evaluation values are compared (step 103). If the evaluation value of the paging channel (PaCH) is better than the evaluation value of the pilot channel (PiCH), the quality evaluation value of the radio channel is changed to the value of the pilot channel (PiCH). PiCH) is updated with the evaluation value and output (step 104).
If the evaluation value of H) is better, the quality evaluation value of the wireless channel is updated with the evaluation value of the paging channel (PaCH) and output (step 105). After the operations of steps 104 and 105 are completed, conversion section 11 stops the operation until the reception period of the next paging channel (PaCH) ends and the above-described step 100 starts.

In the above-described reception period in the standby reception state,
Since the error rate of the paging channel (PaCH) determines the quality evaluation of the radio channel, the signal-to-noise ratio of the pilot channel (PiCH) and the paging channel (PaCH), which affect this, are evaluated, respectively. The deteriorated evaluation value is used as the quality of the wireless line. This is because each of the above channel signals may be independently interfered with each other due to the relationship between the short code phase offsets between base stations and the difference in the combination of code sequence assignments for multiplexing.

FIG. 4 is a flow chart showing the operation of the conversion unit 11 by the control unit 5 in the call state.

In the figure, when the above-described predetermined measurement period τ during which the demodulation unit 4 performs the demodulation operation is completed and the measurement unit 10 outputs the signal-to-noise ratio of the pilot channel (PiCH) and the traffic channel (TCH), the conversion is performed. The unit 11 is activated (step 200), acquires these signal-to-noise ratios (step 201), and obtains the pilot channel (PiCH) and traffic channel (TCH) from the respective look-up tables using the signal-to-noise ratio as an argument. ) To obtain a wireless channel quality evaluation value for the demodulated output (step 202). And
The two evaluation values are compared (step 203), and the evaluation value of the traffic channel (TCH) is
If the evaluation value is better than the evaluation value of (PiCH), the quality evaluation value of the wireless channel is updated with the evaluation value of this pilot channel (PiCH) and output (step 204). Is better, the quality evaluation value of the wireless channel is updated with the evaluation value of the traffic channel (TCH) and output (step 205). And
After the operations of steps 204 and 205 are completed, the conversion unit 1
1 stops the operation until the next predetermined measurement period τ ends and the above-described step 200 starts.

In this way, during the call period, the error rate of the traffic channel (TCH) indicates the quality of the radio channel, and the signal-to-noise ratio of the pilot channel (PiCH) and the traffic (TCH), which affect the error rate, are respectively determined. The quality of the wireless link is evaluated based on the deteriorated evaluation value of the two.

Returning to FIG. 1, the above-described radio line quality evaluation result is provided to the user on the display unit 12 as a graphic display b. The graphic display b is performed, for example, by increasing or decreasing the number of antenna bars in accordance with the evaluation values of three to five levels.

As described above, in this embodiment, the effect on the error rate of the paging channel (PaCH), which is a line control signal for paging, is evaluated in the standby reception state. Since the influence of the traffic channel (TCH), which is a signal, on the error rate is evaluated, the radio wave quality can be monitored by the quality of the wireless line that accurately corresponds to the state of the own station, whether in the standby reception state or the call state. Can be provided to the user.

[0054]

As described above, according to the present invention,
In a CDMA mobile station apparatus in which a plurality of base stations share a carrier frequency, a signal-to-noise ratio for a radio signal from a currently linked base station is reliably evaluated, and the quality of a radio channel is monitored based on the result. Can be provided, even if the interference power from other base stations is increased and the reception level of the radio signal is increased, without being affected by this, with the currently linked base station The quality of the wireless link during the period can be accurately provided to the user.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a mobile station device according to the present invention.

FIG. 2 is a block diagram showing a specific example of a transmission unit of a CDMA base station.

FIG. 3 is a flowchart showing an operation of the control unit in FIG. 1 in a reception period in a standby reception state.

FIG. 4 is a flowchart showing an operation of the control unit in a call state in FIG. 1;

FIG. 5 is a block diagram illustrating an example of a conventional mobile station device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Common antenna for transmission / reception, 2 splitter, 3 Receiver 4 Demodulator 5 Control unit 6 Audio unit 7 Receiver 8 Transmitter 9 Transmitter 10 Measurement unit 11 Conversion unit 12 Display unit 13 Operation unit

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 5K014 AA01 EA01 FA09 FA11 GA01 GA04 HA00 HA10 5K022 EE02 EE22 EE32 5K067 AA03 AA33 BB03 CC10 DD13 DD23 DD25 DD45 EE02 EE10 FF16 FF23 GG11 JJ21 LL01 LL11

Claims (5)

[Claims] 1. A mobile station apparatus for receiving, from a base station, a radio signal obtained by subjecting a multiplexed signal obtained by code division of one or a plurality of call information signals and a control signal of a radio channel to a spread spectrum process using a spread code. Despreading the received radio signal to spectrum and demodulating it to the multiplexed signal assigned to the own station, and from the demodulated multiplexed signal the call information signal assigned to the own station and the state of the own station. Demodulating means for despreading and separating and outputting the control signal and the respective codes used for multiplexing in accordance with the control signal; and the radio signal for each of the control information and the call information signal demodulated and separated by the demodulating means. A mobile station device comprising: evaluation means for evaluating the quality of a line and displaying a state of a radio wave based on the evaluation result. 2. The spread code according to claim 1, wherein a spread code for the spread spectrum processing is different for each of the base stations, and the demodulation means uses a spread code synchronized with a spread code used by the linked base station. A mobile station apparatus for despreading the received radio signal. 3. The measuring unit according to claim 1, wherein the evaluating unit measures a signal-to-noise ratio of the information signal or the control signal output from the demodulating unit. A mobile station apparatus comprising: a conversion unit that converts the signal-to-noise ratio into quality information of a wireless channel and outputs the quality information; and a display unit that displays the quality information output from the conversion unit. 4. The control signal according to claim 3, wherein the control signal includes at least a pilot signal used for searching for a phase of a spread code for the spectrum despreading and a paging signal for calling a mobile station. And evaluating the quality of the radio channel obtained from the signal-to-noise ratio of the pilot signal and the quality information of the radio channel obtained from the signal-to-noise ratio of the paging signal when in the standby reception state. A mobile station device that outputs quality information of a lower quality level. 5. The control signal according to claim 3, wherein the control signal includes at least a pilot signal used for searching for a phase of a spread code for spectrum despreading, and the conversion unit, when in a call state, transmits the pilot signal. The lower of the evaluations of the quality information of the wireless channel obtained from the signal-to-noise ratio of the signal and the quality information of the wireless channel obtained from the signal-to-noise ratio of the information signal assigned to the own station. A mobile station device for outputting quality information.