JPH06268635A - Radio communications equipment and antenna diversity method for the same - Google Patents

Abstract

PURPOSE:To provide an antenna diversity method for reducing the cost of the radio communications equipment, miniaturizing it by simplifying the configuration of a reception system, and exactly selecting an antenna system. CONSTITUTION:At the radio communications equipment, a receiver 50 and a demodulator 60 are integrated into one system. Then, the measurement of received electric field strength, the collection of reception errors or the decision is accurately performed under the control of a microcomputer 82 and a software memory 83 inside a control part 80 of the radio communications equipment so as to connect a first satisfactory antenna 20 to the reception part of one system and based on this result, antenna diversity is performed. Thus, there are effects such as easily selecting/switching the antenna system used for receiving valid data and further preparing an optimum radio communications system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of controlling antenna diversity, which is applied to a radio telephone device or the like which adopts a TDMA / TDD radio communication system.

[0002]

2. Description of the Related Art A radiotelephone device adopting a TDMA / TDD radio communication system is controlled by an antenna diversity method. FIG. 14 shows a conventional example of such a control device. In FIG. 14, reference numeral 1 is a first antenna, 2 is a second antenna, 3 is an antenna changeover switch for switching between the first antenna 1 and the second antenna 2, and 4
Is a transceiver and 5 is a wireless controller. The transceiver 4 includes a first receiver 6, a first demodulator 7, and a second receiver 8
, A second demodulator 9 and first and second receivers 6, 8
Received electric field level comparison unit 10 for comparing received electric field levels of
Further, the reception electric field level comparison unit 10 includes a receiver changeover switch 11 for switching the signal output of the first and second demodulators 7 and 9, and a transmitter 16. The radio control unit 5 includes a reception electric field level storage unit 13 that receives the reception electric field level output from the reception electric field level comparison unit 10 and an antenna switching control unit 14 that controls the antenna switching operation.

The operation of such a conventional control device will be described. In FIG. 14, the antenna changeover switch 3 is changed over in units of reception slots, and the radio control unit 5 controls the changeover based on the transmission / reception operation timing signal 15 prior to reception or transmission. Further, at the time of reception, the reception electric field level comparison unit 10 determines the reception electric field level information from each of the first receiver 6 and the second receiver 8 in bit units of the reception data. Then, the reception electric field level comparison unit 10 makes a decision as to which one of the first and second demodulators 7 and 9 is connected to the first and second receivers 6 and 8, respectively. It is switched by the changeover switch 11 and is output as the reception data 12 in any of the bit unit, the symbol unit or the slot unit.

As described above, in the above-mentioned conventional diversity method of the radio telephone device, the receiver and the demodulator are each constituted by two systems, and the decision for adopting either one of the demodulated data from the two demodulators is made. -It is configured to have a selection circuit.

[0005]

However, in the above-mentioned conventional diversity method of the radio telephone apparatus of the TDMA / TDD communication system, the receiver and the demodulator each require two systems, and the demodulated data from the two demodulators are required. In order to adopt either one of the above, it is necessary to have a reception electric field strength and a demodulation data selection circuit, and the control section becomes complicated, resulting in a problem that the control apparatus has a complicated and expensive structure as a whole.

The present invention has been made in view of the above problems. A first object of the present invention is to simplify the structure of a receiving system to realize a low cost and downsizing of a product, and to omit received data. It is not to provide an excellent wireless telephone device.

A second object of the present invention is, in order to simplify the configuration of the receiving system, configure this receiving system with a receiver of one system so that it can be connected to two antennas, and select an antenna system. Is to provide an antenna diversity method that creates a system configuration that is optimal for reception.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an antenna changeover switch and a transmitter for connecting one of two antennas to one receiver. The receiver is set to one system, the demodulator is also set to one system, and the antenna system switching control is performed for each reception / transmission for each TDMA slot through the wireless control unit in the microcomputer according to the synchronization timing of the synchronization circuit in the control unit. That is the summary.

Further, a microcomputer in the control unit and a software memory for controlling the microcomputer are provided. With this software memory, the electric field intensity received from the receiver is supplied to the radio control unit from the preamble portion of the reception TDMA slot to the frame synchronization ( Unique word) Instructs to make a decision in the signal section. In addition, receive T in software
The gist is that the (CRC) error rate of the effective reception data of the DMA slot is calculated, the optimum antenna system for reception and transmission is selected, and the wireless control unit is instructed.

[0010]

According to the present invention, with the above-described structure, the receiver and the demodulator are integrated into one system, and various information is collected, judged and controlled by the microcomputer, so that the apparatus can be simplified.

Further, in order to maintain the communication quality, the switching timing of the antenna system is set to be before the reception of the valid data so that the received data is not missed and the switching is performed only when necessary. The wireless controller can be controlled by software.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of an embodiment of a wireless telephone device as a wireless communication device according to the present invention. This wireless telephone device is TDMA / TDD
(Time-division multiple access / time-division bidirectional) Wireless communication system is adopted. In FIG. 1, reference numeral 20 is a first antenna for transmitting / receiving a radio signal, 21 is a second antenna for similarly transmitting / receiving a radio signal, 30 is an antenna changeover switch for selecting an antenna system used at the time of transmission / reception, 40 is a transmitter that sends out an audio signal to be transmitted, 50
Is a receiver for receiving the signal sent by radio, 60 is a demodulator for demodulating the received signal, and 70 is a modulator for modulating the transmitted signal. Further, reference numeral 80 is a control unit for controlling the transmission / reception operation of this wireless telephone device, 90 is a voice codec unit for encoding a transmitted voice signal and decoding a received voice signal, and 100 is required for transmitting / receiving other voice signals. It is a peripheral circuit that divides the roles of various functions.

First and second two antennas 20, 2
1 (hereinafter, each system is referred to as an antenna system) is connected with a specified distance secured in order to obtain the effect of diversity. The antenna selector switch 30 is the first antenna 20.
Alternatively, either the second antenna 21 and the transmitter 40 or the receiver 50 are switched and connected. The transmitter 40 is connected to either the modulator 70 or the antenna system. Receiver 5
0 is composed of only one system and is connected to either one of the antenna systems and the demodulator 60. The demodulator 60 is composed of only one system and is connected to the receiver 50 and the control unit 80. Modulator 7
0 is connected to the transmitter 40 and the control unit 80. Control unit 80
Is a synchronizing circuit 81 for controlling the operation timing of the entire wireless telephone device according to this embodiment, a microcomputer 82 for controlling the overall operation of the wireless telephone device, and software (program) necessary for the processing operation of the microcomputer 82. , A channel memory codec section 84 for processing transmission / reception data corresponding to the operating speed of TDMA, an antenna changeover switch 30,
The transmitter 40 and the receiver 50 are configured by a radio control unit 85 that controls the operation according to the operation speed of TDMA. The peripheral circuit 100 is connected to an external device (for example, PSTN network 500). The audio codec section 90 and the peripheral circuit 1
00 has a different circuit configuration depending on the wireless telephone device to which these are applied.

As described above, the receiver 50 and the demodulator 6
Since 0 is configured by one system, the receiving system of the wireless telephone device according to this embodiment has a configuration as shown in FIG. As shown in this figure, the antenna changeover switch 30
Is a parallelogram having four switch pieces 30a, 30b, 30c, 30d on each side so that the first and second antennas 20, 21 can be connected to the receiver 50 of one system. A switch having a (i.e., bridge circuit) configuration is used, and two switches are provided at opposite portions (between 30a and 30b and between 30c and 30d) between the switch pieces.
The two antennas 20 and 21 are connected to each other, and another antenna (30d, 30a and 30
The transmitter 40 and the receiver 50 are connected between (b and 30c). In this antenna changeover switch 30, during data transmission operation, the switch pieces 30a and 30d of the switch pieces 30a to 30d are selectively turned on, and the transmitter 40 is switched to the first antenna 20 or the second antenna 21. Connected. On the other hand, in the data receiving operation, the switch piece 30a of the antenna changeover switch 30 is used.
The switch pieces 30b and 30c of 30 to 30d are selectively turned on, and the receiver 50 is connected to the first antenna 20 or the second antenna 21. The antenna changeover switch 30 has the following five kinds of changeover states. First switching state: transmission / reception pause All four switch pieces are off Second switching state: Antenna 1 transmission Transmitter connected to first antenna Third switching state: Antenna 2 transmission Transmitter connected to second antenna Switching state of 4: antenna 1 reception, receiver connection to the first antenna 5th switching state: antenna 2 reception, receiver connection to the second antenna

The received data demodulated by the demodulator 60 after receiving processing such as detection by the receiver 50 is received by the controller 80.
To the microcomputer 82 therein. Further, the received electric field strength detected by the receiver 50, that is, the received electric field level is sent to the wireless control unit 85 in the control unit 80. The microcomputer 82 includes a CRC error reading unit 821,
A CRC error number accumulating unit 822 that records a count number of how many CRC errors have occurred, and a CRC error number determining unit 823 that determines the number of CRC errors based on the data from the CRC error number accumulating unit 822. There is. On the other hand, the wireless controller 85 controls the receiver 5 for each frame.
The previous frame electric field level storage unit 851 that stores the received electric field level information sent from 0, and the electric field strength comparison unit that compares the electric field level of the current frame by referring to the data of the previous frame electric field level storage unit 851. 852 and the antenna system connection based on the comparison result in the electric field strength comparison unit 852 from the first antenna 20 to the second antenna 21.
Switching control section 8 which outputs a control signal for switching to or from the antenna switching switch 30
And 53. The antenna changeover control signal sets the antenna changeover switch 30 to any one of the above-mentioned five changeover states.

The synchronous circuit 81 incorporated in the control unit 80 will be described in detail with reference to FIGS. 4 and 5. The synchronizing circuit 81 includes a microcomputer interface section 81 for matching the data transfer operation between the frequency dividing / signal generating section 811 having a frequency dividing circuit for generating a reference clock and the microcomputer 82.
2, a network synchronization unit 813 for communicatively connecting the device of this embodiment to other devices, a highway signal control unit 814, and a wireless control signal unit 815.

The frequency division / signal generation unit 291 generates 19.2 MHz (t) in order to generate the reference clock of the wireless telephone device.
cxo) is used as a source oscillation, and a clock required for the operation of each circuit is generated by the frequency dividing circuit. A timing chart for this clock generation is shown in FIG. As shown in this figure, the frequency division / signal generation unit 813 uses, for example, a 9.6 MHz clock and TDMA required for the operation of the microcomputer 82.
A 200 Hz clock (A in FIG. 5) is used as the frame timing, and 1.6 T as the TDMA slot timing.
A clock of kHz (B in FIG. 5), a bit clock timing of the transmission / reception signal of 384 kHz (C of FIG. 5), a symbol clock timing of the transmission / reception signal of 192 k
5 Hz (D in FIG. 5), 128 kHz as clock timing of audio highway signal, 2.4 MHz (E in FIG. 5) as control clock for setting to PLL, and 1.92 MHz as reference clock of channel codec section To do. Also, each clock of transceiver timing (F in FIG. 5) and antenna switching timing (GG in FIG. 5) is generated. The PLL setting control clock is
Both the transmission slot and the reception slot are output so as to take timing about 1/2 slot before the slot. Therefore, of the four reception slots in one frame, for example, P for the second slot
The LL setting control clock is output during the first slot reception, as indicated by E in FIG. Further, as shown by F in FIG. 5, the transceiver timing clock is output at a timing earlier than the slot and PLL setting control clock. As shown by G in FIG. 5, two clocks are output for each slot in the reception section of the frame and one point is output for each slot in the transmission section of the frame.

The microcomputer interface section 812 is an interface block for setting an initial value for the synchronizing circuit 81 from the microcomputer 82, and includes an address line for designating the synchronizing circuit 81 and a data line for setting data. It is composed of read / write control lines.

FIG. 3 is a diagram schematically showing the overall configuration of the wireless communication system when the wireless telephone device according to this embodiment is a base station. In this figure, 300 is a wireless mobile station such as a mobile wireless telephone, 400 is a wireless base station corresponding to the device according to this embodiment, 401 is another wireless base station, and 500 realizes communication by an analog voice signal. The PSTN network is a public switched telephone network, 600 is a comprehensive service digital network that realizes communication by digital voice signals, and 700 is a private branch exchange.

In the network synchronization unit 813, the radio base station 400, which is the radio telephone device according to this embodiment, is a private branch exchange (PB).
X) 700 is a valid block when connected to 700. Here, the radio base station 400 connected to the PBX 700,
Generating a timing signal for synchronizing 401
From this timing, the PBX 700 to the radio base station 40
0/401 will be regularly notified. As a result, the wireless base stations 400 and 401 are synchronized with each other in timing, and it is possible to prevent interference from other wireless base stations 401 in the TDMA transmission / reception slot.

The highway signal control section 814 is for specifying the timing of the audio signal corresponding to each transmission / reception slot, and 32 kBPS is a clock for 4 slots (32 × 4 = 128 kHz).

The radio control signal section 815 is used for surely operating the transmitter 40 and the receiver 50 in the TDMA slot, for example, turning on / off the power supplies of the transceivers 24 and 25 and setting the transmission / reception frequency to the PLL. Is generated and notified to the wireless control unit 85 in the control unit 80. The microcomputer 82 of the present invention has a commercially available 8-bit or 16-bit
A bit general-purpose microcomputer is used. Therefore, the functional block of the microcomputer 82 is the functional block diagram of the manufacturer itself, and a detailed description thereof will be omitted.

Next, the software memory 83 will be described with reference to FIG. Software memory 8 of the present invention
3 has a configuration in which control software is stored in, for example, an EPROM (program memory that can be erased by ultraviolet rays), a flash memory or an EEPROM (electrically rewritable memory), and a RAM (rewritable memory) is used for work. It is taken. As specific storage software, generally, an OS (operating system) or a monitor 831 that manages software control of the entire apparatus is used.
Called software, software generally called BIOS 832 (basic input / output system) of layer 1 level for mediating between hardware and software, link establishing software 833 for establishing a communication phase of layer 2 level, and layer It is composed of three-level network connection setting software 834 and a device-specific application program 835.

The OS and the monitor 831 are control software for maximizing the performance of the microcomputer 82, and execute a program of a control unit generally called a task in accordance with a processing priority determined for each device.
It controls the stop. The BIOS 832 is control software that maximizes the performance of the device hardware, and specifically controls the gate array, serial and parallel input / output ports that are the component parts of the device, and the data block transfer control by DMA. Controls mutual conversion between digital signals and analog signals, timer management control of equipment, and hardware control specific to equipment.
In particular, control software for switching antennas for diversity, detecting communication data (CRC) errors, switching antennas for arithmetic processing, etc. is stored in this block. In addition, the level determination processing program of the electric field strength for each reception TDMA slot is also stored here.

The link establishing software 833 is software commonly applied to the wireless mobile station 300 and the wireless base station 400, is generally layer 2 level software, and is standardized in the communication equipment industry. . This is because, for example, when making a call by telephone, the wireless mobile station 300
From the wireless base station 400 to the wireless base station 400. Also, a CRC error of a communication signal is detected on the communication channel and retry control at that time is performed. The network connection setting software 834 is generally of a layer 3 level, and is largely composed of radio management, mobility management and call control for circuit switching between the link establishing software 833 and the application program 835. Is standardized in the communication industry. The application program 835 is software that defines a device-specific function, and is defined by each manufacturer. This is dedicated to each of the wireless mobile station 300 and the wireless base station 400, and is specified for each wireless telephone device to be manufactured so as to realize the function.

Regarding the extraction of transmission / reception data of the channel codec section 84, the signal format used in the TDMA wireless communication system is standardized in the communication industry.
The signal format is shown in FIGS. As is clear from these figures, in the TDMA wireless communication system,
One radio carrier (frequency) is composed of one frame of 5 ms (millisecond), and this is divided into eight to define a unit called a slot. Therefore, 1 slot is 1.6k
1 Hz of the above wireless carrier is transmission 4
It is composed of a slot (this is called a transmission section) and four receiving slots (this is called a reception section), and actually four communication channels can be set. Then, in FIG. 7, for example, the communication data transmitted from the transmitting side in the transmitting TDMA slot CH1 TX of channel 1 in the wireless carrier 1 frame is detected at the receiving side at the slot timing shown in FIG. 5B. Data transmission / reception such as reception in the reception TDMA slot CH1 RX of channel 1 is performed. FIG. 8 and FIG. 9 show the data structure of 351 frames of communication data transmitted and received by this method. The communication data 35 includes a preamble part 351, a frame synchronization part 352, an effective data part 353 in which data to be transmitted and received such as audio data is incorporated, and a C used for detecting a communication data error.
It is composed of an RC unit 354.

Channel codec section 84 in FIG.
Is, for example, 240 per reception slot from the demodulator 60.
The bit serial signal is taken in based on the slot control timing signal from the synchronizing circuit 81, and whether the received signal is valid or not is determined at the following two points. One is whether the frame synchronization signals (which are called unique words in the communication industry) match. The other is the presence / absence of a CRC error in the valid data portion (for example, voice signal or communication data signal). When the signal is valid, the data of the valid data section is sent to, for example, the audio codec section 90 according to the attribute in the signal, and the microcomputer 82.
May be sent to. Then, substantially the same control is performed for each reception slot, and the processing to be performed differs depending on whether the transmission / reception signal attribute is, for example, a voice signal or a communication data signal.

Further, the channel codec section 84 can be constructed so that if the transmission data is, for example, a voice signal, it is inputted from the voice codec section 90, and if it is a control signal, it is inputted from the microcomputer 82.
It can be sent to the modulator 70 by a transmission timing signal from the synchronization circuit 81 in the MA slot. At this time, in order to have a signal format configuration in the wireless section, the preamble part and frame synchronization (unique word)
A signal, valid data, and a CRC code to the valid data are added. For example, the format is assembled into a 240-bit signal structure.

The radio controller 85 uses the PLL control clock from the synchronizing circuit 81, the transmission / reception control timing, the setting timing to the PLL, and the frequency setting timing based on the frequency data designated in advance by the microcomputer 82 for each reception slot. Based on the above, write control to the PLL is performed. Further, on / off of the transmitter / receiver is controlled in synchronization with the TDMA slot according to the transmission / reception timing from the synchronization circuit 81. Further, the wireless control unit 85 is configured so that the receiver 5
The level of the received electric field is collected at the reception time slot timing from 0, and the microcomputer 82 refers to this to perform the normal processing of the wireless communication of the apparatus and the processing at the time of error. In the antenna diversity method of the present case, the radio control unit 85 determines each reception electric field level for each reception slot, and automatically controls switching to the optimum antenna system for each reception TDMA slot.

The voice codec section 90 has a different structure depending on the apparatus to which it is applied. As an example, when the wireless base station 400 is connected to the analog public network (PSTN network) 500, the block configuration is shown in FIG. 10, and when the wireless base station 400 is the digital public network (ISDN network) 600, the block shown in FIG. When the PBX is connected to the PBX700, this block can be omitted.
00 may have the block shown in FIG. 10 or FIG. In FIG. 10 and FIG. 11, reference numeral 901 is a transcoder circuit having a function of converting the transmission rate of a digital signal, 902 is an echo canceller circuit that eliminates echo and measures against echo of a voice signal, and 903 is a digital voice signal of 64 KBPS. Is a codec circuit that has the function of converting to an analog voice signal or vice versa. Transcoder circuit 901
Is, in order to convert the transmission rate of the digital signal, specifically, it is converted into a 32 KBPS digital audio signal,
Or reverse conversion. The codec circuit 903 can be composed of commercially available parts.

The operation of the radiotelephone device having such a configuration will be described below.

First Operation Example Here, a basic transmission / reception operation of the wireless telephone device according to the present invention will be described. In this embodiment, an example of operation during communication when the device is the radio base station 400 and is connected to the PSTN network 500 will be described with reference to the configuration diagram of FIG. The peripheral circuit 100 is connected to the PSTN network 500. Originating operation from the wireless mobile station 300 or PS
After the communication protocol is established with the wireless base station 400 by the incoming call from the TN network 500 and the communication becomes possible, the wireless base station 400 receives the signal through one of the first defined antennas (the second antenna 21). The microcomputer 82 in the control unit 80 controls the antenna changeover switch 30 by the wireless control unit 85 by the software memory 83 so as to start the reception. The signal received by the second antenna 21 is received by the demodulator 60 via the receiver 50, and is synchronized by the frame synchronization (unique word) signal. Etc.) to the control unit 80 and the voice codec unit 90. The channel codec unit 84 in the control unit 80 synchronizes with the demodulator 60 according to the reception TDMA timing.
The received data and the reception result are received and relayed to the microcomputer 82. Audio codec section 90
Converts the transmission rate of the audio signal from the channel codec unit 84 and converts it into an analog signal and sends it to the peripheral circuit 100. The peripheral circuit 100 is a PSTN network 50.
PST the analog audio signal at the signal level corresponding to 0
Output to the N network 500. The error detection of the received signal is performed by the error detection unit 841 of the channel codec unit 84, which is read by the CRC error reading unit 821 of the microcomputer 82 and the CRC error number storage unit 82.
2 and the CRC error number determination unit 823 determines the number.

The transmission from the radio base station 400 is performed by the PSTN network 5
A channel codec in which the peripheral circuit 100 level-converts the analog audio signal from 00, the audio codec section 90 receives this, converts it into a digital signal, converts it into a transmission rate in a wireless section, and outputs it to the channel codec section 84. The unit 84 controls transmission in advance according to an instruction from the microcomputer 82 in synchronization with the timing of transmission TDMA.
Send a send signal to 0. The modulator 70 performs modulation by a specified modulation method (for example, π / 4 shift QPSK), but prior to this, the wireless control unit 85 that controls the transmission of the transmitter 40 is instructed by the microcomputer 82 to transmit TDMA. According to the timing, the first antenna 20 or the second antenna 21 is connected to the transmitter 40 as an antenna for transmission. As a result, the modulated transmission data is transmitted to the wireless mobile station 300 side via the transmitter 40. When the wireless base station 400 is connected to the ISDN network 600 or the PBX, the voice codec section 90 or the peripheral circuit 1
The circuit configuration of 00 corresponds to a digital signal.

As described above, according to the first embodiment, the receiver 24 and the demodulator 60 can be integrated into one system, and the device can be constructed at low cost.

Next, when the radiotelephone device of the present invention is the radio base station 400 and is connected to the PSTN network 500, the antenna and the antenna are used in order to make this device an optimum radio system for communication.
Variations of various operations for performing diversity will be described.

Second Operation Example In this operation example, the reception electric field strength is collected and determined at a prescribed timing of the reception TDMA slot, and an appropriate antenna system is switched for subsequent effective data reception. To do. The operation of the received electric field strength measurement is shown in FIGS. In FIG. 8, the received electric field strength is measured at the preamble portion and the frame synchronization portion of the received TDMA slot of channel 1. FIG. 9 shows specific electric field strength measurement timings, electric field strength determination timings, and antenna switching timings. The preamble signal section and the frame synchronization (unique word) signal section also make a comparison determination with the received electric field strength of the reception TDMA slot up to the previous frame. Subsequent switching to the antenna system used for receiving valid data is performed "only when necessary" in the frame synchronization (unique word) signal section. The criterion for determining the necessity of switching the antenna system is when the value of the electric field strength is higher than the measured value of the received electric field strength up to the previous frame. By not always switching the antenna system, the frame synchronization (unique word) error of the received data can be reduced, and the device configuration is less likely to lose synchronization.

In the actual reception operation, first, in the first frame, the first antenna 20 starts receiving the reception TDMA slot, and the radio control section 85 measures the reception electric field strength.
The first antenna 20 also receives the valid data. The received electric field strength obtained in this receiving operation is stored in the previous frame electric field level storage unit 851. # 1 and # 2 in FIG.
Represents a receiving antenna system of the first antenna 20 or the second antenna 21. Next, in the second frame, the second antenna 21 starts receiving the reception TDMA slot and the radio control unit 85 measures the reception electric field strength, and the reception electric field strength obtained by this and the first antenna 20 first. The received electric field strength at the time of reception is compared by the electric field strength comparing section 852 of the wireless control section 85. As a result, since # 1 ≧ # 2, the reception antenna switching instruction is output from the antenna switching control unit 853 to the antenna switching switch 30, and the antenna switching switch 30 switches the antenna system to receive valid data. The first antenna 20 is selected and valid data is received by the first antenna 20. The received electric field strength obtained in this receiving operation is also stored in the previous frame electric field level storage unit 851, as in the case of the first frame.

Similarly, in the third frame, the first frame is again displayed.
The antenna 20 receives the reception TDMA slot to measure the reception electric field strength, and the reception electric field strength obtained thereby is compared with the reception electric field strength previously received by the second antenna 21. As a result, since # 2 ≧ # 1, the antenna system is switched here, the second antenna 21 is selected to receive valid data, and the second antenna 21 receives valid data. In the fourth frame, the reception TDMA slot is received again by the second antenna 21 and the reception electric field strength is measured, and the reception electric field strength obtained by this and the reception electric field when the first antenna 20 previously received it are received. Compare with intensity. As a result, since # 2 ≧ # 1, the antenna system is not switched, the second antenna 21 is selected to receive valid data, and the second antenna 21 receives valid data.

As described above, according to the antenna diversity method, the microcomputer 8 in the controller 80 is
2 and the control of the software memory 83, the radio control unit 85 measures the reception electric field strength of the reception TDMA slot and compares the reception electric field strength of the reception TDMA slots up to the previous frame with the preamble unit 351 and the frame synchronization unit. Subsequent control of switching to the antenna system used for receiving valid data can be easily performed with the frame synchronization signal, and the device configuration is flexible and has fewer reception errors based on the received electric field strength of the received signal in real time. be able to.

In this receiving operation, the received electric field strength of the received TDMA slot is a specified value (for example, 60).
It is also possible to add a process of not performing antenna switching for reception of valid data when dBμ) or more. As a result, the wireless controller 8 is controlled by the microcomputer 82 and the software memory 83 in the controller 80.
5 indicates that when the value of the received electric field strength in the receiving TDMA slot is equal to or greater than the specified value and the error of the received signal is hardly generated, the antenna system is not switched when the valid data is received, and the synchronization error of A device configuration that is unlikely to occur can be provided.

Third Operation Example This operation example is for a synchronization error and CR obtained at the time of reception.
The microcomputer 82 manages error information of received data such as a C error, and attempts to switch to an appropriate antenna system under a certain condition. The processing flowcharts in this operation example are shown in FIGS.
It is shown in.

In FIG. 12, when the receiving operation is started, the microcomputer 82 determines whether the current antenna system is the first antenna 20 system or the second antenna 21 in the processing step (hereinafter simply referred to as step) 201. This reception, which memorizes whether or not it is a system, is started by alternately switching two antenna systems for each TDMA slot, and the electric field strength is measured. Antenna 20, 2
The switching control of No. 1 is performed by the antenna switching control unit 853 of the wireless control unit 85 based on the transmission / reception timing signal.
In order to perform the storage processing of step 201, the working memory of the microcomputer 82 secures an area for a frame of a prescribed time (for example, 100 frames for 1 second) for two antennas. Then, the microcomputer 82 updates the oldest CRC error information up to that time to the latest error information (step 20).
2). In order to update this error information, two areas for storing the total number of CRC errors are secured in the microcomputer 82, and an area for storing the number of continuous CRC errors is secured. After updating the error information in step 202, it is checked whether or not there is a CRC error in the current reception operation (step 203), and if there is a CRC error, the number of CRC error slots of the same antenna system is added to obtain the latest error. The number of CRC errors per second is calculated (step 204). Then, it is checked whether or not there is a continuous CRC error in the same antenna system (step 205), and if there is a continuous CRC error, the continuous error counter is incremented by 1, that is, incremented (step 206). It is checked whether or not the number of consecutive errors is N, which is a predetermined number of times (step 207). Then, if it is determined in step 207 that the CRC error has occurred N times in succession, the microcomputer 82 outputs a signal instructing antenna switching to the wireless control section 85 (step 208), and a series of error detection for the TDMA slot, Then, the antenna switching process is terminated and the process returns to the reception of the next TDMA slot. In the wireless control unit 85, a reception antenna switching instruction is output from the antenna switching control unit 853 to the antenna switching switch 30 based on the control signal from the microcomputer 82, and the antenna switching switch 3
0 switches the antenna system, and subsequent reception of valid data is performed by the switched antenna.

If it is determined in step 203 that there is no CRC error, the microcomputer 82
Shifts to step 209, compares the number of CRC errors between the first antenna 20 system and the second antenna 21 system, issues an instruction to select the antenna with the smaller CRC error, and detects the error. And the antenna switching process ends. Then, as a result of the processing of step 209, when it is necessary to switch the antenna, the wireless control unit 85 switches the receiving antenna from the antenna switching control unit 853 to the antenna switching switch 30 based on the control signal from the microcomputer 82. An instruction is output, the antenna changeover switch 30 switches the antenna system, and subsequent reception of valid data is performed by the switched antenna. If it is determined in step 205 that there is no continuous CRC error in the same antenna system, the process proceeds to step 210, the continuous error counter is initialized, and then the process proceeds to step 209. Further, even if it is determined in step 207 that the number of consecutive errors has not reached the predetermined N times, the process proceeds to step 209, and then the error detection and antenna switching process is terminated.

The process of FIG. 13 is performed when the wireless control unit 85 collects and determines the received electric field strength (level).
The received electric field level of the two antenna systems is above the specified value,
And when there is almost no difference, CR up to the previous frame
It is intended to switch the antenna based on the C error information. In this process, when the receiving operation is started, the microcomputer 82 makes a step 221.
In, it stores whether the current antenna system is the first antenna 20 system or the second antenna 21 system. This reception is started by alternately switching the two antenna systems for each TDMA slot, and the electric field strength is measured. The switching control of the antennas 20 and 21 is performed by the antenna switching control unit 853 of the wireless control unit 85 based on the transmission / reception timing signal. Microcomputer 82 then verifies the CRC error in the current valid received data (step 222). Then, after the CRC error verification in step 222, C is detected in the current receiving operation.
It is checked whether there is an RC error (step 22).
3) If there is a CRC error, it is checked whether there is a continuous CRC error in the same antenna system (step 22).
4) If there is a continuous CRC error, the continuous error counter is incremented by 1, that is, incremented (step 2
25) Further, it is checked whether or not the number of consecutive errors is N, which is a predetermined number of times (step 226). Then, when it is determined in step 226 that the CRC error has occurred N times in succession, the microcomputer 82 outputs a signal instructing antenna switching to the wireless controller 85 (step 227) to detect a series of errors in the TDMA slot. Then, the antenna switching process is terminated and the process returns to the reception of the next TDMA slot.
In the wireless controller 85, the microcomputer 82
An antenna switching control unit 853 outputs a reception antenna switching instruction to the antenna switching switch 30 based on the control signal from the antenna switching switch 30. The antenna switching switch 30 switches the antenna system, and subsequent reception of valid data is performed by the switched antenna. .

If it is determined in step 223 that there is no CRC error now, the microcomputer 8
2 shifts to step 228, compares the number of CRC errors between the first antenna 22 system and the second antenna 21 system, issues an instruction to select the antenna with the smaller CRC error, and detects the error. , And the antenna switching process ends. Then, as a result of the processing in step 228, when it is necessary to switch the antenna, the wireless control unit 85 switches the receiving antenna from the antenna switching control unit 853 to the antenna switching switch 30 based on the control signal from the microcomputer 82. An instruction is output, the antenna changeover switch 30 switches the antenna system, and subsequent reception of valid data is performed by the switched antenna. If it is determined in step 224 that there is no continuous CRC error in the same antenna system, the process proceeds to step 229, the continuous error counter is initialized, and then the process proceeds to step 228. Further, even when it is determined in step 226 that the number of consecutive errors has not reached the predetermined N times, the process proceeds to step 228, and then the error detection and antenna switching process ends.

As described above, according to the antenna diversity method, the microcomputer 8 in the controller 80 is
2 and the control of the software memory 83, receive TDM
There is an advantage that the reception error in the A slot can be easily collected and the error can be determined, and the optimum antenna system to be used for the subsequent reception TDMA slot can be selected.

In the error detection, the frequency of occurrence of a reception error (for example, CRC error) in the reception TDMA slot of the same antenna system is counted over a plurality of frames, and the number of times is defined by the reception TDMA slot of a certain frame. Then, it is possible to control to switch from the next reception TDMA slot to the other antenna. Furthermore, when the transmission operation and the reception operation are alternately performed, the transmission TDM is performed in the current frame.
The antenna system used in the A slot is the reception TD immediately before.
It can also be controlled to be the one used when valid data of the MA slot is received. This has the advantage that the optimum antenna for transmission can be easily selected and the transmission can be controlled to be extremely efficient.

[0048]

As described above, according to the present invention,
Since the receiver and the demodulator can be integrated into one system in the wireless communication device, the structure of the device can be simplified and the cost can be reduced. Also, the received electric field strength is measured by controlling the microcomputer and software memory in the control unit.
It collects or determines reception errors with high accuracy and performs antenna diversity based on this, so it is easy to select and switch the antenna system used to receive valid data, and create an optimal wireless communication system. It is possible to obtain various effects.

[Brief description of drawings]

FIG. 1 is a block diagram of a wireless communication device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a receiver configuration of the embodiment.

FIG. 3 is a functional block diagram showing a wireless communication system in which the wireless communication device of the embodiment is incorporated.

FIG. 4 is a block diagram showing a configuration of a synchronization circuit incorporated in the wireless communication device of the above embodiment.

FIG. 5 is a timing chart illustrating timings of various clocks generated by the synchronization circuit.

FIG. 6 is a block diagram showing the configuration of a software memory incorporated in the wireless communication device of the above-described embodiment.

FIG. 7 is a TDMA / T adopted by the wireless communication device of the present invention.
Transmission and reception timing chart of DD wireless system

FIG. 8 is a diagram for explaining a frame structure of communication data in the TDMA / TDD wireless system and a reception electric field strength measuring operation in the present invention.

FIG. 9 is a diagram for explaining the reception field strength measurement operation of the communication data in more detail according to the present invention.

FIG. 10 is a block diagram showing a configuration of a voice codec unit of the embodiment for a PSTN network.

FIG. 11 is a block diagram showing a configuration of an audio codec unit of the embodiment for an ISDN network.

FIG. 12 is a flowchart showing an antenna diversity operation by CRC error detection according to the present invention.

FIG. 13 is a flowchart showing an antenna diversity operation according to another CRC error detection in the present invention.

FIG. 14 is a block diagram showing an example of a conventional TDMA / TDD wireless communication device.

[Explanation of symbols]

 20, 21 Antenna 30 Antenna changeover switch 35 Communication data 40 Transmitter 50 Receiver 60 Demodulator 70 Modulator 80 Control section 81 Synchronous circuit 82 Microcomputer 83 Software memory 84 Channel codec section 85 Radio control section 90 Voice codec section 100 Peripheral circuit 300 wireless mobile station 400, 401 wireless base station 500 PSTN network 600 ISDN network 700 private branch exchange

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[Procedure amendment]

[Submission date] April 6, 1993

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

[Figure 3]

[Figure 5]

[Figure 6]

[Figure 9]

[Figure 10]

[Figure 4]

[Figure 7]

[Figure 8]

FIG. 11

[Fig. 12]

[Fig. 13]

FIG. 14

Front page continuation (72) Inventor Tsuneharu Sawamura 4-3-1, Tsunashima-higashi, Kohoku-ku, Yokohama-shi, Kanagawa Matsushita Communication Industrial Co., Ltd. (72) Inoue Odahara Tsunashima-higashi, Kohoku-ku, Yokohama-shi, Kanagawa 4-3-1, Matsushita Communication Industry Co., Ltd. (72) Inventor Naoya Morita, 4-3-1, Tsunashima East, Kohoku Ward, Yokohama City, Kanagawa Prefecture Matsushita Communication Industry Co., Ltd. (72) Inventor Masafumi Ryakuzumi Matsushita Communication Industrial Co., Ltd. 4-3-1, Tsunashima Higashi, Kohoku Ward, Yokohama City, Kanagawa Prefecture

Claims (9)

[Claims] 1. A transmitter, a modulator for modulating transmission data, a receiver for receiving a signal, a demodulator for demodulating the reception data, and two antennas for catching transmitted and received radio waves.
The receiver and the circuit of the demodulator have an antenna changeover switch that selectively connects and connects each of the two antennas to a transmitter or a receiver, and a control unit that controls a transmission / reception operation and an antenna changeover operation. A TDMA / TDD wireless communication device in which each has a single system, and an antenna is selected by the control unit at the time of reception. 2. A transmitter, a modulator for modulating transmission data, a receiver and demodulator for one system for receiving and processing a signal, two antennas, and two antennas for the transmitter or receiver. The TDMA / TDD wireless communication device is configured by an antenna changeover switch that is selectively switched and connected, and a control unit that controls the transmission / reception operation and the antenna changeover operation. Measure the received electric field strength,
An antenna diversity method in which the antenna system with the larger received electric field strength is selected for reception. 3. A transmitter, a modulator for modulating transmission data, a receiver and demodulator for one system for receiving and processing a signal, two antennas, and two antennas for the transmitter or receiver. The TDMA / TDD wireless communication device is configured by an antenna changeover switch that is selectively switched and connected, and a control unit that controls the transmission / reception operation and the antenna changeover operation. An antenna diversity method characterized by selecting a current receiving antenna system based on error information of communication data. 4. In addition to the measurement of the reception electric field strength for each TDMA reception slot, error information of communication data for each TDMA reception slot is collected, and a current reception antenna system is selected based on both factors. The antenna diversity method according to claim 2. 5. The measurement result of the electric field strength of the reception TDMA slot until the immediately preceding frame is switched by switching the antennas of the two systems to an antenna system different from the reception TDMA slot of the previous frame each time the reception electric field strength measurement of the reception TDMA slot is started. 5. The antenna according to claim 2, wherein one of the antenna systems most suitable for subsequent effective data reception is selected by comparing the measurement result of the received electric field strength of the current reception TDMA slot. -Diversity method. 6. The reception TDMA is performed by measuring the electric field strength of the reception TDMA slot and subsequently selecting the reception antenna system.
3. The antenna diversity method according to claim 2, wherein the preamble portion in the received signal of the slot is performed, and the switching control of the antenna system is performed only when necessary in the frame synchronization (unique word) signal portion immediately after. 7. The receiving TDMA slot is configured to switch to the other antenna system in the same receiving TDMA slot of the immediately following frame when a receiving data error is detected a predetermined number of times in the same antenna system. The antenna diversity method according to claim 3 or 4. 8. The antenna diversity method according to claim 2, wherein the switching of the antenna system is stopped when the received electric field strength is equal to or higher than a specified value in the reception TDMA slot. 9. The antenna system used in the transmission TDMA slot is selected so that the antenna system that has been effectively receiving data in the reception TDMA slot is used. 3. The antenna diversity method described in 3.