JP2001160775A - Radio communication system with broadcast function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To constitute a radio communication system which can simultaneously execute broadcast and make a call in a communication system with broadcast function, which gives the service of broadcast and the call to a telephone subscriber through private exchange, and to construct the radio communication system without increasing construction cost trough the use of the facility of an existed cable broadcast telephone system. SOLUTION: A radio base station 25 receiving the simultaneous broadcast command of emergency from a broadcast controller 211 connected to the private exchange 22 through the private exchange has a procedure for transmitting a broadcast incoming call request by using a control channel. A subscriber radio terminal 23 has a means for making a response to the procedure. A means for allocating a time slot and a radio frequency (channel), which are previously decided, is disposed as the broadcast warning channel. In the construction of the radio communication system, the metal cable of an existed party line-type cable broadcast telephone system is used for a line between the private exchange 22 and the radio base station 25. Thus, the system can economically be constructed by using the existing communication facility. Then, the call by broadcast and a telephone can simultaneously be executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio communication system with a broadcasting function, more specifically, a plurality of radio base stations (WCS) connected to a private branch exchange (PBX) by wire, and a radio communication from the radio base station. The present invention relates to a radio communication system with a broadcasting function, which is accommodated in a reachable area and has a plurality of subscriber radio terminals communicating with the radio base station by the radio TDMA method.

[0002]

2. Description of the Related Art Conventionally, as a communication broadcasting system which secures the broadcasting property and provides a communication service, there is a joint subscription type cable broadcasting telephone system which is introduced and adopted by local governments, agricultural cooperatives and the like. This is installed in a broadcast control device connected to a private exchange and a subscriber's house, and each is branch-connected to a fixed telephone and a fixed telephone connected to the private exchange by two pairs (one pair) of metal cables. It is composed of a speaker device.

[0003] As shown in FIG. 1, a conventionally known joint subscription type cable broadcasting telephone system includes a broadcast control device 11,
The private switchboard 12 and the subscriber's house 13 each have a fixed telephone 131 and a broadcast receiving speaker 132 branch-connected to the fixed telephone 131, respectively. Pair (1
The pair is connected by a metal cable 14.

[0004] The broadcast is notified by sound from a microphone 111 attached to the broadcast control device 11. In the above-mentioned wired telephone system, for example, when one subscriber 13A is using a fixed telephone during a call or when performing a broadcast service from the broadcast control device 11, the subscriber 13B receives a broadcast through a speaker. Calls from fixed telephones are not possible. That is, since the joint subscription type wired broadcast telephone system uses a metal cable jointly by a plurality of subscribers, other subscribers cannot make a call (call loss) while talking or broadcasting on the same metal cable. Has disadvantages.

[0005] In order to solve this drawback, there is a part where an individual subscription type cable broadcasting telephone system is introduced. The individual subscription type wired broadcast telephone system is provided with a pair of two metal cables for a fixed telephone and a broadcast speaker installed at a subscriber's house for receiving a broadcast broadcast from a broadcast controller. In order to sound, two pairs of metal cables are further required. Therefore, two pairs of metal cables are required for each subscriber. This is because when renewing the cable broadcasting telephone system from the joint subscription system to the individual subscription system, the metal cable was newly laid,
Increase the complexity of construction and construction costs.

Therefore, without increasing construction costs,
In addition, a new system that enables simultaneous broadcasting and achieves both call (communication) and broadcast, that is, enables reception of broadcast even during a call is required. In addition, when using the metal cable, it is necessary to eliminate communication failure due to aging of the metal cable.

As a wireless telephone system, TDAM
As an example of a wireless access system employing the A method, PH
There is an S system. The PHS system uses the standard RCR
As shown in STD-28, full-duplex communication is enabled by four downlink time slots and four uplink time slots. At this time, one of the four time slots is used for transmission and reception of control information, and three time slots that can be used simultaneously for a call (communication) are three time slots. In other words, if three subscribers talk (communicate) at the same time,
The slot becomes busy, and no new call (communication) is accepted, resulting in a call loss.

It is conceivable to use the above-mentioned conventional PHS system in a radio communication system with a broadcasting function. However, there is a problem that it becomes impossible to broadcast an emergency broadcast when the slot is busy.

[0009] As another conventional communication system technology, there is a technology relating to group incoming to a terminal device disclosed in Japanese Patent Laid-Open Publication No. Hei 10-30442. this is,
It is composed of a PHS master unit connected to a communication line and a slave unit connected to the master unit. A group number is registered in the master unit in advance, and group reception is performed for the slave unit. Applying this conventional technology to a wireless communication system with a broadcast function,
When used for group broadcasting, it is necessary to register a plurality of group numbers in advance for an unspecified number of wireless base stations installed outdoors. At this time, it is necessary to correspond to the group number to be registered and the installation location of the wireless base station, which complicates the installation work. In addition, when a new subscriber is generated, a group number registering means such as downloading to each wireless base station is required. Therefore, for the terminal device of the wireless communication system, the number management of the group incoming (broadcast),
It is necessary to assign a group number by a simple method.

[0010]

SUMMARY OF THE INVENTION Accordingly, a first object of the present invention is to provide a radio communication system with a broadcasting function for providing broadcasting and telephone communication (communication) to a subscriber of a radio terminal via a private exchange. Broadcast and call are possible at the same time,
For example, it is an object of the present invention to realize a wireless communication system with a broadcasting function that enables a telephone call even during broadcasting.

Another object of the present invention is to realize a radio communication system with a broadcasting function which can economically achieve the first object by utilizing many of the existing facilities such as a joint subscription type cable broadcasting telephone system. It is to be.

A third object of the present invention is to realize a radio communication system which can notify all subscribers of an emergency broadcast or the like in a radio system originally intended for communication employing the TDMA system. is there.

A fourth object of the present invention is to provide a wireless communication system employing the TDMA system without being restricted by time slots that can be used simultaneously by the wireless base station, that is, when the wireless base station is busy with time slots and broadcasting. An object of the present invention is to realize a wireless system capable of notifying a subscriber of an emergency broadcast or the like without disconnecting a normal call already in a call in an assigned time slot.

[0015] A fifth object of the present invention is to realize a radio communication system which enables broadcasting in a unit of a group constituted by subscribers.

[0015]

In order to achieve the above object, a radio communication system with a broadcasting function according to the present invention comprises: a broadcast control device for inputting a broadcast type and an audio signal to be broadcast to a private exchange; A wireless communication system having a plurality of wired base stations connected by wire and a plurality of subscriber wireless terminals installed in a wireless coverage area of the wireless base station, wherein the wireless base station and the subscriber wireless terminals are , One frame is composed of the number of target slots of up n (integer) time slots and down n time slots, location control, incoming call and outgoing call are controlled by the control information channel, and other time slots are used. Means for communicating telephone communication and broadcast audio signal communication in a wireless TDMA system, wherein the subscriber wireless terminal reproduces an encoded signal of the broadcast audio signal. Coding of speech talk path and the telephone, a structure having a telephone communication channel for performing decoding.

In a preferred embodiment of the present invention, the broadcast control device has PB signal generating means corresponding to a broadcast instruction and a broadcast type, and the private branch exchange includes a first codec unit for coding the broadcast audio signal. A second encoding unit for encoding the encoded signal of the first codec unit and the telephone call signal.
Encoding section, a radio base station interface section for converting a signal of the second encoding section into a signal format to be sent to the radio base station, and detecting the PB signal to control the radio base station interface section. A signal processing unit, wherein the radio base station receives a broadcast instruction from the broadcast control device, and includes means for transmitting a broadcast call request signal to the subscriber wireless terminal through a control channel.

Further, the second encoding section encodes the encoded signal of the first codec section into a lower-speed encoded signal, and the third encoding section encodes the telephone call signal. A fourth encoding unit that encodes an encoded signal having the same speed as the encoded signal of the third encoding unit, and a telephone call signal encoded by the fourth encoding unit that is encoded by the fourth encoding unit. And a multiplexing unit for multiplexing coded signals of the third coding unit and the fourth coding unit. The signal processing unit controlling the radio base station interface unit outputs one of the output of the multiplexing unit and the output of the fifth encoding unit in accordance with the TDMA slot use state of the radio base station by a speech call. A processing unit for selecting and generating a transmission signal to the radio base station;

The above-mentioned radio communication system with a broadcasting function may construct a new radio communication system. However, the radio communication system with the broadcasting function is used as a line for connecting the private exchange and the plurality of radio base stations by wire to an existing wired telephone system. By using a paired cable, the construction cost can be reduced.

When a pair cable used in the existing wired telephone system is used, there is a concern that the pair cable may be deteriorated at an early stage. However, the private switchboard sends the wireless base station an SI (start of system-related consultation). ) Sending a frame, activating a timer, and executing the S
Until the acknowledgment signal SQ for the I frame is received,
By retransmitting the SI frame, counting the number of retransmissions, examining the number of retransmissions that cannot be received in a certain period, and determining the quality of the line between the private branch exchange and the radio base station, the problem of aging can be solved. Solvable.

The broadcast types include emergency broadcast, simultaneous broadcast, and group unit broadcast. The group unit broadcast is performed only in a specific group unit of a plurality of subscriber wireless terminals. By assigning a number to each group unit of the private branch exchange and the subscriber wireless terminals, the broadcast in the group unit is performed. This is realized by providing a means for performing the operation.

The communication means using the wireless TDMA system, when instructed by the type of the broadcast, the wireless base station sends out a broadcast call request using a control channel, and the subscriber wireless terminal transmits the request to the subscriber. Respond to Also, as a broadcast audio signal notification, a predetermined channel allocation for voice communication between the private branch exchange and the radio base station is set, and a radio time slot between the radio base station and the subscriber radio terminal is set in advance for broadcasting. It has defined time slot allocation means.

Further, when the radio base station receives the broadcast instruction when the radio base station is busy with the time slot,
A signal of a normal call that is already in a call in a broadcast allocation time slot is changed to a low-speed voice coding / decoding, and a low-speed voice coding / decoding transmission rate of a voice communication path previously allocated for broadcasting is changed. The radio base station divides the received signal into audio coded data portions of time slots previously allocated for broadcasting, and allocates the multiplexed data. The subscriber radio terminal transmits the divided audio coded and decoded signals. Each is allocated to the above-mentioned broadcast communication path and the above-mentioned communication path.

[0023] Other features and advantages of the present invention will become more apparent from the following description of embodiments of the invention. Note that the broadcast audio signal includes music, an alarm sound, and the like in addition to audio, but in the embodiment, the audio signal will be described as audio.

[0024]

FIG. 2 is a block diagram showing an embodiment of a radio communication system with a broadcasting function according to the present invention.
And the signal format used for the system (b)
Is shown.

As shown in FIG. 2A, the present radio communication system instructs three types of broadcasts: emergency, simultaneous, and group.
Broadcast control device 21 for broadcaster to input audio signal such as voice
1, a function of discriminating the types of the three types of broadcasts specified by the broadcast control device 211, a function of performing circuit switching, and a function of connecting to a radio base station. , A maintenance terminal device 29 for rewriting and newly registering the data of the above-mentioned subscriber, and a private exchange 22 connected to the private exchange 22 by a pair of metal cables 24. Recommendation G. (abbreviated as CCITT) 961 (ping-pong method), various control information,
The wireless base station 25 communicates with wireless terminals provided in a plurality of subscriber homes 23 using four channels of 32 kbit / s audio data signals.

The radio base station 25 and the subscriber home 23 connect the antenna 251 of the radio base station 25 and the subscriber home antenna 27 by radio, and as shown in FIG. 5ms for 4 time slots 262
And performs communication. The time slot 263 is assigned to a control channel for transmitting and receiving control information, and the other three time slots are used for transmitting and receiving 32 kbit / s audio signal data.

A plurality of subscribers accommodated in the radio base station 25, for example, the subscribers 23A, 23B, and 23C simultaneously start a call and are busy with time slots using three time slots for the call. Time slot allocation for new calls, means to be able to allocate broadcasts, and priority to broadcasts due to urgent contents when time slots allocated to broadcasts are already used for normal calls Need to be allocated. That is, when it is necessary to disconnect a normal call during a call, there is provided a means for allocating a broadcast without disconnecting a call already in a normal call in a broadcast allocation time slot. Details of this means will be described later.

In the subscriber's house 23, an antenna 27, a subscriber's wireless terminal 23 having a subscriber's telephone number and broadcast data are stored.
3, a fixed telephone 231 connected to the wireless terminal 233, and a subscriber broadcast receiving speaker 232. That is,
The subscriber wireless terminal has a broadcast communication path for reproducing an encoded signal of a broadcast audio signal and a telephone communication path for encoding and decoding telephone sound. The fixed telephone may be a GIII facsimile machine.

The construction of the wireless communication system of the present embodiment is as follows.
The main parts of the metal cable 14 and the private exchange 12 used in the conventional joint subscription type cable broadcasting telephone system are as follows:
Metal cable 24 for connection between private branch exchange 22 and wireless base station 25 in the wireless communication system with a broadcasting function according to the present embodiment.
The wireless base station 25 is provided on the metal cable 14 and the subscriber terminal 132 is replaced with the subscriber wireless terminal 233, thereby being constructed at an economical cost.

The radio base station 25 is used to accommodate a plurality of subscribers 23.
That is, it is necessary to secure the cell radius and the call volume in consideration of the conventional joint-subscription cable broadcasting telephone system. In Japan, 10 subscribers can be accommodated in a wireless reach of a radius of 400 m. The wireless reach of a radius of 400 m is realized by setting the antenna ground height of the wireless base station 25 to 7 m, making the antenna gain 4 dBi, and omnidirectional, and ideally configuring a circular cell.

Since the public PHS sets the call volume per subscriber to about 0.01 erl, the call volume is set to 0.05 erl (3 minutes / 1 hour) which is equal to or greater than the same. Therefore,
The total call volume when one wireless base station 25 accommodates 10 subscribers is 0.05erl × 10 subscribers = 0.5erl. In the above example, the radio base station 25 has three time slots for communication, that is, a traffic volume equivalent to three subscriber lines is obtained. Here, the call loss rate caused by an error peculiar to the wireless communication is set to 0.01, and when the Erlang B-type table is used, 0.
6 erl is obtained. Therefore, 10 subscribers total call volume 0.05erl
To be satisfied.

Regarding the reuse of the metal cable 14, communication failure between the private branch exchange and the wireless base station due to the aging of the metal cable is expected. For this reason, the wireless communication system with a broadcasting function of the present embodiment is provided with a connection device (to be described in detail later) between a private branch exchange and a wireless base station for eliminating aging of the metal cable.

The configuration of main equipment used in the radio communication system with a broadcast function of the above embodiment will be described below. FIG.
FIG. 1 is a diagram illustrating a configuration of an embodiment of a broadcast control device. The broadcast control device 211 instructs the private exchange of (1) emergency broadcast to be absolutely notified to the subscriber, (2) normal simultaneous broadcast, (3) group-based broadcast, and (4) broadcast type of the end of the broadcast. (Notification) means.

The broadcast control device 211 includes the microphone 3
Microphone amplifier 303 for amplifying the analog audio signal from P.01 to a predetermined level, adder 305 for analog adding the output signal of microphone amplifier 303 and the output signal of PB signal generator 317, and the output of adder 305 A private exchange interface unit 307 for connecting signals to the private exchange 22 via a line 309, an emergency switch 311 for instructing emergency broadcast, and a simultaneous switch 32 for instructing simultaneous broadcast
1, a switch group 3 for indicating each broadcast type, including a group # 1, a group # 2 switch 312 for instructing broadcast in a group unit, and an end switch 314 for instructing end of broadcast
10 and a switch determination unit 315 connected to a push button (hereinafter abbreviated as PB) signal generation unit 317 in response to an instruction signal for instructing output of a PB signal corresponding to each of the broadcast types.
And a power supply unit 319 that generates power for supplying power from the commercial power supply 320 to each unit of the broadcast control device 211.
Note that power supply lines to each unit are omitted.

The emergency switch 311 may be connected to, for example, a weather observation rain gauge or an anemometer alarm determination switch, and used as an automatic alarm in abnormal weather. The microphone microphone 301 may be used as an automatic sound transmission device for automatic sound transmission in an emergency.

FIG. 4 is a diagram showing the configuration of one embodiment of the private branch exchange 22. The private branch exchange 22 includes a broadcast control device 211.
And PB corresponding to each broadcast type connected by connection line 309
A broadcast control device interface unit 402 including a PB detection unit for detecting each of the signals, and a CCITT G.2 converting a broadcast analog audio signal from the broadcast control device 211 into a 64 kbit / s PCM signal. 711-based PCM codec unit 404 (hereinafter abbreviated as PCM codec) 4
04, the output signal of the PCM codec unit 404 is transmitted to the radio base station 25 and the CCITT G. 961 ping-pong system, and a plurality of wireless base station interface units 406 that perform bidirectional communication of control information and voice signals with the wireless base station 25
To determine the broadcast type indicated by the broadcast control device 211 from the PB signal detection result 411 from the interface unit 402, rewrite the subscriber ID 412, the subscriber number 411, and the group number 413 in the storage device 414, and newly register them. Connected to the maintenance terminal device 29 (FIG. 1) via a line 407 and executes the operation and control of the entire private branch exchange 22.
U408 and an audio signal from the radio base station 25 are input via the interface unit 406 and the line 416,
In accordance with the instruction of U408, the vacant channels of the channels B1 to B4 are searched, and the respective radio base station interface units 40 are searched.
6 and a selector unit 415 for selecting and assigning, and an address / data bus 409 for connecting and communicating between the respective blocks.

FIG. 5 shows the radio base station interface unit 4.
FIG. 6 is a block diagram showing a configuration of an embodiment of the present invention. The radio base station interface unit 406 converts the output PCM signal 501 of the PCM codec 404 in the private exchange 22 into an ITU-TG.
It is connected via a line 416 to a codec unit 502 that converts the data into LD-CELP conforming to 728 16 kbit / s and allocates it to the B1 channel of the interface between wireless base stations, and a selector 415 of the private branch exchange 22. Is allocated to the B1 channel of the interface between the radio base stations, and
LD multiplexed with D-CELP signal by multiplexing section 504
-When the CELP codec unit 512 and the simultaneous broadcast instruction, P
The output PCM signal of the CM codec 404, during a normal call during non-broadcasting, the selector 415 in the private exchange and the line 4
ITU-T G.16, which is connected via B.16 and used for normal calls and assigned to the B1 channel of the interface between radio base stations. 726-compliant 32 kbit / s ADPCM codec section 516, selector section 415 and line 416
And ITU-TG G. connected to channels B2 to B4 of the radio base station interface. 7
26 kbit / s ADPCM codec section 521
Multiplexing section 504 for multiplexing input / output signals of codec sections 502 and 512 (multiplexing section 504 has 16 kbit
The signal is converted into a signal of / s × 2ch = 32 kbit / s and assigned to the B1 channel of the interface between the radio base stations. )
And the input / output signal of the multiplexing unit 504 and the input / output signal of the codec 516 are fetched, and the input / output signal of the multiplexing unit 504 is selected at the time of each broadcast according to the instruction of the CPU 526. Selector unit 5 for selecting input / output signals and connecting to line interface unit 508
06.

The line interface unit 508 communicates control information with the radio base station 25 and is connected to an LAPD controller unit 519 for decomposing and assembling control signals (Dch). The control signal and the ITU-TI. 430, 2
The frame is converted into a frame structure of B + D (1B = 64 kbit / s, D = 16 kbit / s) and connected to a network (hereinafter abbreviated as OCU) 510 for ping-pong transmission. In this embodiment, 32
Since it employs kbit / s ADPCM, it normally has a transmission capacity of 4B.

Further, the dual port RAM 524 is
One of the ports is connected to an address / data bus 409 in the private exchange 22. Transmission of information indicating a broadcast type and transmission of other control information are performed from the private exchange 22. The other port is connected to an address and data bus 525 and transmits information indicating the broadcast type. That is, the CPU 40 of the private branch exchange 22
8 and the CPU 52 of the wireless base station interface unit 406
6 with the CPU 6.

The CPU 526 executes the program stored in the ROM 527, acquires the information indicating the broadcast type from the dual port RAM 524, and controls the above-mentioned respective blocks via the address / data bus 525.
In addition, it has a function of monitoring the communication state of control information with the radio base station 25 and determining the number of retransmissions of control information for avoiding communication failure due to aging of a metal cable or the like. The RAM 528 stores the number of retransmissions.

FIG. 6 shows the storage device 41 in the private branch exchange 22.
FIG. 4 is a diagram illustrating a configuration of an example of the fourth embodiment. Storage device 414
Is the subscriber I representing the name of the subscriber corresponding to the address.
D61, a subscriber telephone number 62 corresponding to the subscriber ID 61, which is the number of a telephone set connected to the subscriber wireless terminal, and a group corresponding to the subscriber ID 61 to which each subscriber belongs. Is stored in the storage unit of the group number 63.

The subscriber ID 61, telephone number 62, and group number 63 of the storage device 414 can be electrically rewritten by the maintenance terminal device 29, and each number corresponding to the subscriber ID 61 can be rewritten to enable new registration. . Further, the storage device 414 stores a telephone number 62 for transmitting the telephone number individually held by each of the wireless terminals of the subscriber 23 to the private branch exchange 22 as the position registration via the wireless base station 25 and a wireless base station ID 64 for receiving the position registration. And can correspond. Here, the position of the storage device 414 will be described for a normal call and for each broadcast type.

A normal call is a call between telephones connected to a subscriber wireless terminal, and the number used at this time is the subscriber telephone number 62. That is, the calling telephone is
The private exchange 22 specifies the called subscriber's telephone number, retrieves the storage device 414 from the called subscriber's telephone number, and receives the incoming call connected to the subscriber's wireless terminal via the corresponding wireless base station. Call the destination telephone.

At the time of emergency or simultaneous broadcasting, the broadcast control device 211
, The private exchange 22 instructs all radio base stations 25 to start broadcasting. At the time of group broadcast, when the broadcast type is instructed from the broadcast control device 211,
The private branch exchange 22 searches the storage device 414 for the wireless base station 25 to which the designated group number 63 belongs, and instructs the wireless base station 25 of the search result to start broadcasting.

FIG. 7 is a block diagram showing the configuration of one embodiment of the radio base station 25. The configuration of the radio base station 25 is basically substantially the same as that conventionally known. The radio base station 25 transmits / receives data to / from the subscriber radio terminal 233 2
A transmitting / receiving unit, a frequency conversion unit, a π / 4 shift Q for realizing wireless access with the antenna 27 of the subscriber's wireless terminal, which are connected in a diversity manner by the antenna 251
A radio unit 702 composed of PSK modulation / demodulation and the like;
02, a transmission / reception data line 704, a control line 703 for reducing power consumption of a radio unit and setting data for a frequency conversion unit.
And disassembly and assembly of TDMA frame and time slot signals, as well as CRC, scramble,
Controller 705 that performs scrambling on the
And ITU-TI. 16kbit / s DC conforming to 430
h, 64 kbit / s Bch, (the Bch is, in this embodiment,
Line interface unit 707 that performs disassembly and assembly of layer 1 signals composed of 32 kbit / s 4ch
, Line interface unit 707 and ITU-TI. 4
CCITT G.30, which is connected in a signal format and is connected to a private exchange 22 via a line 24. Digital Service Unit (DSU) based on the 961 ping-pong system
711, a CPU 713 for generating various timer values and executing a program, and a ROM 71 for storing the program
4 and RA for temporarily storing data during program execution
M715 and Dch from the private branch exchange 22 to decode the broadcast control data of the present embodiment,
A LAPD controller unit 708 that transmits the control data for broadcast from the CPU 713 to generate the Dch, and an address / data bus 71 that transmits instructions and data according to the program of each block.
8 and a power supply unit 716 that generates power to be supplied to each unit from the commercial power supply line 717.

Radio section 702 and controller section 705
Performs simultaneous connection of four time slots. That is, one time slot is allocated for a control channel and three time slots are allocated for a call (communication), and at the same time, a call (communication) with three subscriber wireless terminals can be performed. Further, the line interface unit 70
7 is a clock for synchronizing the controller unit 705 and the radio unit 702. Of the 4B channels, the B1 channel is 32 kbit / s ITU-TG. 726 compliant ADPC
M or one channel of ITU-T G.M. It is connected by two channels of LD-CELP conforming to 728. The above B
B2 to B4 channels other than 1 channel are 32 kbit / sI
TU-TG. 726-compliant ADPCM data. The Dch is connected to the line interface units 707 and 1
Connected at 6 kbit / s.

FIG. 8 is a block diagram showing the configuration of one embodiment of the subscriber wireless terminal 233. Subscriber wireless terminal 233
Is a omni-directional antenna 27 for wirelessly accessing and transmitting to and from the wireless base station 25, and a wireless unit 802 including a transmitting / receiving unit, a frequency converter, a π / 4 shift QPSK modulator / demodulator for realizing wireless access, and the like. , TDMA frame and time slot signal disassembly, assembly, CR
C, scrambling, TDMA controller section 805 (the TDMA controller section is connected to the radio section 802 and the transmission / reception data 804 via the control line 803 for reducing the power consumption of the radio section and setting data for the frequency conversion section). ), An LD-CELP codec unit 809 connected to the controller unit 805, and a PCM codec unit 81 to which an output of the codec unit 809 is input.
7, an analog audio signal output from the PCM codec section 817, a speaker interface section 821 that converts the signal into a drive signal for the speaker 232 and adds the signal to the speaker, and an LD-CEL that decodes the output of the controller section 805.
P codec section 810 and TDMA controller section 805
An ADPCM codec section 811 connected to the output side, a selector section 814 connected to the output side of the codec sections 810 and 811 and selected by an external control and added to the codec 818, and an analog audio output from the PCM codec section 818. A signal is input, converted to a drive signal for the telephone 231, and added to the telephone 232 by the telephone interface unit 822 and the address data bus 830.
CPU 828, ROM 831, RAM 83 interconnected with DMA controller 805, selector 814
2 and a power supply unit 833 that generates power to be supplied to each unit from the commercial power supply line 834.

Here, the radio section 802 and the controller section 80
5 is synchronized with a time slot constituted by the radio base station 25. Further, the output of the controller unit 805 is the first communication path of the single communication path at the time of emergency, simultaneous, and group broadcasting.
It is used as a system and a second system of a full-duplex communication channel of a normal communication channel.

At the time of various types of emergency, simultaneous, and group broadcasting, the codec unit 809 operates according to ITU-TG. 728 16kbit / s
The LD-CELP signal is decoded, and the LD-CELP encoded data is converted to ITU-TG. 64kbit / compliant with 711
Decode to sPCM signal. PCM codec section 817
Decodes the 64 kbit / s PCM signal and outputs an analog audio signal to the speaker interface unit 821. The speaker interface unit 821 has a function that allows the subscriber to arbitrarily set the volume of the speaker 232 and a function that sets the maximum volume regardless of the volume setting according to an instruction 812 of the CPU 828 during an emergency broadcast.

The codec section 810 enables normal communication during various broadcasts irrespective of time slot assignment, and multiplexes ITU-TG. 7
It encodes and decodes a normal speech sound signal conforming to 2816 kbit / s LD-CELP. Codec section 81
1 is a TDMA controller unit 805 and a line 8 when broadcasting is not being performed.
07, and connected to ITU-T G.07. 726 32kbit / s
It encodes and decodes an audio signal during a normal call conforming to ADPCM.

The selector section 814 converts the input / output signal of the codec 810 into the PCM codec section 818 in accordance with an instruction from the CPU 828 during each of the emergency, simultaneous, and group broadcasts.
In addition, when broadcast is not being performed, A
The input / output signal of the DPCM codec 811 is applied to the PCM codec 818. PCM codec section 818
Decodes a 64 kbit / s PCM signal and inputs and outputs an analog audio signal. The telephone interface unit 822 detects on-hook and off-hook of the telephone 231, transmits a ringer signal for outputting a ringing sound from the telephone when receiving a call, a power supply unit for supplying power to the telephone, and a PB signal indicating a destination telephone number from the telephone. It consists of a PB receiver to detect.

Further, the subscriber's wireless terminal 233 is connected to an external device such as a timer and a personal computer via a line 827.
Asynchronous serial communication connection via the
It has a serial interface unit for rewriting subscriber telephone numbers and group numbers in the system, and performing new registration. A CPU 828 for executing the procedure of the present embodiment, a program including the procedure of the present embodiment, a telephone number assigned to each subscriber, and a ROM 831 for storing an electrically erasable group number for calling during group broadcasting. RAM 832 for storing the current state of the subscriber's wireless terminal, that is, the state of a normal call, the state of receiving a broadcast, the state of a normal call being broadcast, and the like. Done.

The operation of one embodiment of the above wireless communication system will be described below. FIG. 9 is a diagram showing a sequence between the private exchange and the wireless base station at the time of power-on and system reset for monitoring the state of the metal cable between the private exchange and the wireless base station in the wireless communication system.

The radio base station interface section 406 of the private branch exchange 22 and the line interface section 707 of the radio base station 25 operate at the time of power-on and reset. 96
Training according to I.1 The power ON and reset sequence (901) including the confirmation of the establishment of the layer 1 synchronization of 430 frames is executed.

After the completion of the sequence 901, the radio base station 25
The LAPD controller unit 708 transmits a line allocation request (abbreviated as SABME) frame via the line interface unit 707 and the DSU 711 (902).
The LAPD unit 519, which has received the SABME frame via the OCU line interface unit 508 of the wireless base station interface unit, generates a UA signal which is an acknowledgment signal for the SABME frame (903), and transmits the UA signal via the line interface unit 508 and the OCU 510. I do.
The above is the procedure for Layer 2.

Next, the CP of the radio base station interface unit
U526 generates a Layer 3 message and sends the LAPD
Instruct the unit 519 to transmit an SI (start of systematic consultation) frame. The LAPD section 519 which has received the instruction generates an SI frame and sends it out via the line interface section 508 and the OCU 510 (904).
The LAPD controller unit 708 that has received the SI frame via the DSU unit 711 and the line interface unit 707 notifies the CPU 713 of a Layer 3 message. Upon receiving the layer 3 message, the CPU 713 in the radio base station performs SQ (ACK for SI frame)
It generates a frame layer 3 message and instructs the LAPD unit 708 to generate an SQ frame. Upon receiving the instruction, the LAPD unit 708 generates an SQ frame and sends it out via the line interface unit DSU 711 (9).
05).

The LAPD unit 708, which has received the SQ frame via the DSU of the radio base station interface unit and the line interface unit, notifies the CPU 713 of the Layer 3 message included in the SQ frame, and
3 ends the test after receiving the layer 3 message (906).

Details of steps 904 to 905 of the above operation of the radio base station interface unit 406 are shown in FIG.
Will be described. After transmitting the SI frame (904), the CPU 5
26 activates a timer T1 of about several seconds (90
7). After the activation of the timer T1, the expiration of the timer T1 is monitored (908). After the timer T1 expires, X indicating the number of times of retransmission of the SI frame is incremented (909). It is determined whether or not the SQ frame has been received after the increment (910). When the SQ frame is received, the number of retransmissions X is R
The result is stored in the AM 528 (912), and the test ends 906. At this time, if the signal has not been received, it is compared with n indicating the limit of the number of retransmissions X (911).
The procedure returns to the I frame transmission procedure. At this time, if X becomes equal to n, that is, if the retransmission limit has been reached, it is judged that the metal cable between the private branch exchange and the radio base station has deteriorated remarkably and cannot be used (913).

The number of retransmissions stored in RAM 528 is used for communication of control information using Dch between the private branch exchange and the radio base station. That is, from the private branch exchange 22 to the radio base station 25
, The control information is always transmitted for the number of times stored in the RAM 528.

As described above, stable communication can be performed without being affected by the deterioration of the metal cable between the private branch exchange and the wireless base station.

FIG. 10 shows a transmission signal format of a radio section between a radio base station and a subscriber radio terminal in one embodiment of the radio communication system according to the present invention.

The TDMA frame 100 of the radio base station 25
No. 1 constitutes one frame with a channel 1005 having a time width of 5 msec, and broadcasts at 100 msec intervals 1004 using the control channels 1006 and 1007. The control information at the time of broadcasting according to the present embodiment uses a control channel. 1
The frame is a Tx time slot n (n =
1-4) 1008, Rx time slot n for reception
(N = 1 to 4) 1009. One of the four time slots is used for transmission / reception of a control channel, and three time slots include a call including broadcasting.
Assign for (communication). In this embodiment, Tx time slot 1 and Rx time slot 1 are used for control channel transmission and reception.

The TDMA frame 1002 of the subscriber wireless terminal 233 synchronizes with the wireless base station 25 (1003), and receives control channels on channels 1012 and 1013. One frame includes a transmission Tx time slot n (n =
1 to 4) 1011, reception Rx time slot n (n =
1-4) 1010. That is, when the wireless base station 25 transmits, the wireless terminal 233 receives the signal, and when the wireless base station 25 receives the signal, the wireless terminal 233 transmits. One of the four time slots is used for transmission / reception of a control channel, and three time slots are allocated for a call (communication) including broadcasting. In this embodiment, time slot 1
Are used for control channel transmission and reception, and time slot 2 is used as a broadcast assigned time slot. The broadcast assignment time slot may be arbitrarily determined by an individual system.

Next, the procedure of simultaneous broadcast and group broadcast such as emergency will be described with reference to FIGS. FIG.
Shows a physical interface at the time of broadcasting in one embodiment of the wireless communication system according to the present invention.
Broadcast number 1 based on PB signal sequence from broadcast control device 211
11 is transmitted. The physical interface 113 between the private branch exchange and the radio base station is CCITTG. 961 or ITU-TI. 430, two 64 kbit / sec communication channels (Bch) and one 16 kbit / sec control channel (Dc
h). However, in the wireless communication system of the present embodiment, since the normal communication channel is set to 32 kbit / sec,
Four channels B1 to B4 can be used.

One radio base station and a plurality of subscriber radio terminals are connected by a TDMA radio 114 composed of four time slots n (n = 1 to 4). In this embodiment, each subscriber wireless terminal 2
33 transmits / receives control channels to / from the wireless base station 25 using the time slot 1.

The private exchange 22 that has received the broadcast instruction from the broadcast control device 211 instructs the radio base station 25 to broadcast using the control channel (Dch). After receiving the broadcast instruction, the wireless base station 25 instructs each subscriber wireless terminal 233 to start broadcasting using the control channel of the time slot 1.

As described above, after the broadcast control device 211 instructs the subscriber wireless terminal 233 to start broadcasting, the communication path 112 from the microphone 301 connected to the broadcast control device 211 is connected and the broadcast is started. The broadcast communication path is transmitted to the radio base station 25 using the B1 channel 117 in the private branch exchange, and the radio base station 25 uses time slot 2 to allocate for broadcasting and broadcast to the subscriber radio terminal. The voice 116 is transmitted.

Next, the configuration of the B1 channel 117 allocated for broadcasting will be described.

Normally, as described above, the audio coding method is as follows.
ITU-T G. 32kbit / s ADP based on 726
Calls are enabled by the CM 118. However, as described in the above-mentioned "Prior Art", when the subscriber uses all of the call time slots of the radio base station for the call, the broadcast cannot be allocated. Therefore, in this embodiment, when broadcasting is performed, ITU-T G. By using the 16 kbit / s LD-CELP system conforming to 728, that is, 32 kbit / s ADPCM is converted to 16 kbit / s during broadcasting.
LD-CELP # 1 for normal call, LD-CELP # 2
Is changed to two channels 119 for broadcasting, so that broadcasting can be performed even when all time slots are used for communication.

Referring to FIG. 12, the configuration of a time slot for communication between the radio base station and the subscriber radio terminal when the audio coding scheme in the B1 channel 117 at the time of broadcasting is changed will be described.

FIG. 12 shows a format 121 of a physical time slot for communication between a radio base station and a subscriber radio terminal in the radio system of the present invention, which is described in RCR STD-28. 32kbit / s ADPCM for calls
The encoded data 123 is an I channel (160 bits) 1
22.

At the time of broadcasting, the 160 bits of the I channel are
LD-CELP encoded # 1 data 12 for normal call
4, and 80 bits of LD-CELP # 2 encoded data 125 are allocated for broadcasting. That is, during a normal call, 32 kbit / s ADPCM coding is used, and at the time of broadcasting, the B1 channel and time slot 2 which are preferentially allocated to broadcasting are set to 16 kbit / s LD-CEL.
By allocating the P2 channel, both the broadcast and the normal communication can be achieved even when the radio base station is busy with the time slot during the normal communication.

Hereinafter, the operation of the subscriber wireless terminal during broadcasting will be described. FIG. 13 shows a broadcast sequence in the embodiment of the wireless communication system. This will be described in detail with reference to the format of the wireless time slot shown in FIGS. 14 and 15 and the broadcast sequence of the subscriber wireless terminal shown in FIG. Broadcasting includes a broadcast call from the wireless base station to the subscriber wireless terminal (procedure 1), a broadcast channel establishment request from the subscriber wireless terminal to the wireless base station (procedure 2), and a broadcast from the wireless base station to the subscriber wireless terminal. Channel assignment (procedure 3) is performed by a synchronous burst transmitter for time slot synchronization from the wireless base station to the subscriber wireless terminal (order 4). Here, a description will be given focusing on a sequence at the time of an emergency broadcast.

During an emergency broadcast , the broadcaster presses the emergency switch 311 of the switch group 310 of the broadcast control device 211.
Switch judging unit 31 that detects pressing of emergency switch 311
5 requests the PB signal generation unit 317 to transmit a PB signal corresponding to the emergency broadcast. Upon receiving the request, the PB signal generator 317 generates a PB signal corresponding to the emergency broadcast and sends it to the private exchange 22 via the private exchange interface 307 (1301). The operations up to this point are as follows, except that the PB signal corresponding to each broadcast type is transmitted.
The same applies to all broadcasts and all broadcasts and broadcast end.

The broadcast controller interface unit 402 of the private branch exchange 22 that has received the PB signal from the broadcast controller 211 notifies the CPU 408 of the PB signal detection result. Upon receiving the notification, the CPU 408 sends the address / data bus 4 to the wireless base station interface unit 406.
09 to indicate the start of an emergency broadcast requesting a call instruction for all subscribers. At this time, simultaneous broadcasting is performed in the same manner as described above. At the time of group broadcasting, the radio base station accommodating the group number, that is, the radio base station interface unit 4
06 to start broadcasting.

Upon receiving the emergency broadcast start instruction, the radio base station interface unit 406 transmits the emergency broadcast SETUP.
A signal is transmitted to the wireless base station 25 using the control Dch (1
302). At this time, a group number is designated during group broadcasting in which a group is designated for broadcasting.

Line interface 508, LAPD
The radio base station 25 that has received the SETUP signal via the controller unit 519 shifts to the procedure 1.

(Procedure 1) The CPU 713 of the radio base station 25 that recognizes the start of the broadcast starts the timer T1 (130).
4) The PCH is transmitted to the subscriber wireless terminal at the control channel transmission timing (1303). PC
H is composed of a format 141 shown in FIG. 14 based on RCR STD-28. The PCH is transmitted as I data (62 bits) 142. At the time of broadcasting, I data is transmitted with the content shown in 1421. That is, during emergency broadcast, simultaneous broadcast or group broadcast, the PS numbers are all “0”, the extended call service type is “0100” during emergency broadcast, “0101” during simultaneous broadcast, and the group number is , All “0” at the time of simultaneous broadcast such as emergency, and designated group number “x” at the time of group broadcast.
xx ".

The radio base station 25 continues to transmit the PCH 141 at the control channel transmission timing until the timer T1 expires. Here, the timer T1 is set such that a call loss rate due to a radio-specific error is 0.01, and ten subscriber radio terminals are connected to one radio base station at the same timing.
Considering that H is waiting, (1 / 0.01) * 100 msec = 10 sec (1), it is set to 10 sec (PCH transmission 100 times). This is to avoid a situation where a plurality of subscriber wireless terminals accommodated in the wireless base station cannot receive the PCH 141. After transmitting the PCH, the radio base station 25 waits for a response transmission after the PCH 141 reception of the subscriber radio terminal 233 is completed.

(Procedure 2) The subscriber wireless terminal 233 is
6 operates in the sequence shown in FIG. The CPU 828 of each of the plurality of subscriber wireless terminals receiving the PCH 141,
The TDMA controller unit 805 extracts I data (62 bits) from the demodulated data from the wireless unit 802, and determines whether the extended call service type 144 is “0100” or “0101” from the extraction result (161).
When it is “0100” or “0101”, it is determined whether or not the group number 145 is all “0” (1
62), if all "0", emergency broadcast or
Recognize as broadcast. At this time, if the group number 145 is not all “0”, it is stored in the ROM 831.
It is compared with its own group number, and it is determined whether or not the broadcast is a group broadcast addressed to itself (163). here,
If it is not a group broadcast addressed to itself, the PCH is ignored. At this time, if a group number addressed to itself is designated, broadcast reception is started (164).

Next, it is determined whether or not the extended call service type 144 is "0100" (166). When the determination result is "0100", the volume for the speaker volume setting provided in the speaker interface unit 821 in the subscriber wireless terminal is maximized regardless of the setting of the subscriber (167), and the broadcast audio reception is performed. prepare. At this time, if the extended call type 144 is “0101”, the broadcast audio reception is immediately prepared.

The CPU 828 in the subscriber's wireless terminal that has shifted to the broadcast receiving process generates a USCCH (broadcast channel request) signal, and adds a unique word (UW) such as a synchronization signal in the TDMA controller 805 to the wireless unit. Transmission is performed using the control channel (1305). At this time, the broadcast channel probability request and allocation format to be transmitted are constituted by the USCCH format 151 shown in FIG.
I data (34 bits) 152 is transmitted, and the data content is 7 bits 153 in the first octet as “000000”.
1 ". USCCH 151 can be optionally used by the user. At this time, the subscriber wireless terminal
Connect a broadcast channel.

(Procedure 3) The radio base station 25
Out of the USCCHs transmitted by the plurality of subscriber wireless terminals 233 received through the U.S.C.
H is enabled, and the timer T2 is started at the same time as sending out the USCCH (broadcast channel assignment) (1306) (13).
07). The radio base station 25 continues to transmit the USCCH at the control channel transmission timing time until the timer T2 expires. The value of the timer T2 is 10se, which is the same as the expression (1).
c.

(Procedure 4) The broadcast channel allocation US
The subscriber wireless terminal 233 that has completed the reception of the CCH waits for the synchronization burst of the procedure 4 with the time slot number and the radio frequency according to the broadcast channel allocation USCCH from the radio base station 25 (1308). By the synchronization burst from the wireless base station 25, the subscriber wireless terminal 233 synchronizes the time slot allocated to the broadcast, connects the communication path, and shifts to the broadcast. The radio base station 25 steals the I data portion of the call (communication) slot even during broadcasting and transmits the synchronization burst at a period that does not impair the audibility in order to prevent the reception failure of the synchronization burst by the subscriber radio terminal 233. to continue. After completing the above-described procedures 1-4, the private branch exchange 22 starts transmitting broadcast audio. That is, in the radio base station interface unit 406 of the private branch exchange 22, the broadcast audio encoding codec unit 502 is assigned to the B1 channel, and the line interface unit 508 and the OCU 510 are allocated.
A voice signal for broadcast and normal call is transmitted through the radio base station 25
Connect to As described above, the private exchange 22 and the wireless base station 25 form a communication path using the B1 channel.

Next, the line interface unit 7 connected to the B1 channel via the DSU 711 of the radio base station 25
07 connects the B1-channel speech coded signal to the TDMA controller unit 708. The TDMA controller unit 708 uses the time slot 2 to wirelessly connect the communication path with the subscriber wireless terminal 233 in the format shown in FIG.

The time slot for communication is stored in the radio section 802.
The TDMA controller unit 805 in the subscriber wireless terminal 233 connected via the interface extracts the I (160-bit) part and connects the 80-bit LD-CELP codec # 2 to the codec 802 on the broadcast communication path. The speech coded data connected to the codec section 809 is P
It is connected to the CM codec and converted to an analog audio signal.

The analog audio signal for broadcasting is input to the speaker interface unit 821. When an emergency broadcast is received, the speaker interface
, The maximum volume is specified regardless of the volume setting value of the subscriber, and is output to the speaker 231. According to the above procedure, each broadcast including the emergency broadcast is performed. here,
The operation of a subscriber wireless terminal during a normal call and a broadcast assignment during a normal call using a broadcast assignment time slot 2 between a wireless base station and a subscriber wireless terminal during a broadcast incoming call will be described.

The subscriber radio terminal transmits the broadcast PCH to the radio section 8.
02, and the TDMA controller 805 extracts the I part. The CPU 828 of the subscriber wireless terminal sends a signal to the selector unit 814 from the ADPCM codec 811 currently connected to the normal communication communication path to the LD-CELP.
It requests the codec unit 810 to switch and connect.
Upon receiving the request, the selector unit 814 connects the LD-CELP codec unit 810 to the normal communication channel, and at the same time, the TDMA controller unit 805 sets the I (160 bi)
t) The part is extracted, and 80 bits of LD-CELP # 1 are connected to the LD-CELP codec unit 810 connected to the normal communication channel. The speech coded data connected to the LD-CELP codec section 810 is connected to a PCM codec section 818, converted to an analog voice signal, and converted to a telephone 23 via a telephone interface 822.
Added to 1.

As described above, the broadcast can be allocated without disconnecting the normal call which is already in a call in the broadcast time slot. Further, according to the same procedure as described above, the broadcast can be started without being affected by the time slot busy of the radio base station in the normal call.

Returning to FIG. 13, the operation at the end of the broadcast will be described. The operation of each component device at the end of the broadcast is substantially the same as the operation at the start of the broadcast. The broadcast end notification by the PB signal from the broadcast control device 211 is received (130).
9) The private branch exchange 22 notifies the wireless base station 25 of DISC, which is control information for disconnection, using Dch (131).
0). The DISC is connected to a line interface unit 707,
The wireless base station 25 that has received the data via the LAPD controller unit 708 recognizes the end of the broadcast by the CPU 713 and starts the timer T3 (1312). CPU 713
Generates a wireless channel disconnection signal, and the controller 7
At 08, a signal such as a UW (unique word) is added and transmitted from the wireless unit 702 (1311). At this time, the format of the radio channel disconnection signal is RCR STD-2.
It is a thing of 8 regulations. The wireless channel disconnection signal continues to be transmitted until the timer T3 expires. The value of the timer T3 is 10 seconds, which is the same as the result of the expression (1).

The subscriber wireless terminal 233 includes a wireless unit 802,
After the CPU 828 recognizes the reception of the wireless channel disconnection signal through the TDMA controller 805, the broadcast communication path is closed, and the broadcast reception ends.

Next, with reference to FIGS. 8, 10, and 13, a description will be given of the allocation of a normal call during and during broadcast. The broadcast assignment between the wireless base station 25 and the subscriber wireless terminal 233 is as described above. The radio base station 25 transmits a broadcast call command PCH at control channel transmission timings 1006 and 1007. At this time, the timer T1 is started, so that PCH transmission for other normal call incoming calls cannot be performed during that period. The wireless base station 25 is connected to the subscriber wireless terminal 23.
During broadcast paging by the broadcast incoming PCH for broadcast call 3, the normal call PCH 1007 is allocated to the normal call PCH 1007 at an arbitrary interval of the broadcast PCH 1006 without allocating all control channel transmission timings to the broadcast call PCH. Make an assignment.

The subscriber wireless terminal 233 is, as described above,
The TDMA frame is synchronized with the radio base station 25. The subscriber wireless terminal 233 receives the received PCH by the wireless unit 802, extracts Ich (62 bits) by the TDMA controller unit 805, and extracts the CPU
28 first determines whether or not the extended service type 144 is “0100” (161 in FIG. 16). If not, it is determined that the PCH is a normal incoming call PCH, and the process proceeds to normal call processing (165). The normal call processing is performed by the RCR ST
This method is based on D-28.

At this time, the telephone interface unit 822 of the subscriber wireless terminal generates a ringer signal,
31 is caused to ring. After confirming the ring tone of the telephone 231, the subscriber goes off-hook on the telephone and starts talking. That is, the subscriber does not particularly operate (consciously),
A normal call can be made at the start of the broadcast and during the broadcast.
At this time, the time slot 2 or the time slot 4 is allocated between the wireless base station and the subscriber wireless terminal because the time slot 2 is allocated for broadcasting. However, as described above, even if the time slot 2 is being used for broadcasting, the broadcast audio encoding method is changed to 16 kbit / s.
By performing LD-CELP, time slot 2 can be allocated to a normal call. That is, by providing the subscriber's wireless terminal with a broadcast communication path and a normal call communication path, a normal call can be allocated and a normal call can be made even when a broadcast call is received or a broadcast is being received.

The present invention is not limited to the above embodiment, but can be changed according to the system implementation environment, such as time slot allocation, coding and decoding means (codec) configuration, and the number of bits. it is obvious.

[0096]

As described above, the wireless communication system with a broadcast function via the private branch exchange of the present invention can perform the same call as that of the main broadcast. A telephone call can be started, and even if the line is busy, emergency broadcast, simultaneous broadcast, group-based broadcast, and the like can be started. That is, both broadcasting and telephone communication can be achieved.

Further, many of the existing facilities such as the existing co-subscription type cable broadcasting telephone system are used, and in particular, by using the cable between the existing private exchange and the subscriber terminal, the communication system introducer can be used. The burden can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing a conventional joint subscription type cable broadcast telephone system.

FIG. 2 is a diagram showing a configuration of an embodiment of a wireless communication system with a broadcast function according to the present invention.

FIG. 3 is a diagram showing a configuration example of a broadcast control device used in the embodiment.

FIG. 4 is a diagram showing a configuration example of hardware of a private branch exchange used in the embodiment.

FIG. 5 is a diagram showing a configuration example of hardware of a wireless base station interface unit provided in a private branch exchange used in the embodiment.

FIG. 6 is a diagram showing a configuration example of a storage device provided in a private branch exchange used in the embodiment.

FIG. 7 is a diagram showing a configuration example of a wireless base station used in the embodiment.

FIG. 8 is a diagram showing a configuration example of a subscriber wireless terminal used in the embodiment.

FIG. 9 is a diagram showing an error check sequence between the private branch exchange and the radio base station used in the embodiment.

FIG. 10 is a diagram showing a format of a wireless section between a wireless base station and a subscriber wireless terminal in the embodiment.

FIG. 11 is a diagram showing a physical interface of each component device at the time of broadcasting of the wireless communication system in the embodiment.

FIG. 12 is a diagram showing a format of a communication time slot between a wireless base station and a subscriber wireless terminal of the wireless communication system according to the embodiment.

FIG. 13 is a view showing a broadcast control sequence of each component device at the time of broadcasting of the wireless communication system in the embodiment.

FIG. 14 is a diagram showing a format of a PCH for broadcast incoming call at the time of broadcasting of the wireless communication system in the embodiment.

FIG. 15 shows a broadcast channel establishment request and a USCCH for allocation in broadcasting of the wireless communication system in the embodiment.
FIG.

FIG. 16 shows P of the wireless communication system in the embodiment.
FIG. 6 is a diagram showing a sequence of a subscriber wireless terminal when receiving a CH.

[Explanation of symbols]

211: Broadcast control device 22: Private exchange 23: Subscriber home 231: Fixed telephone 232: Broadcast reception speaker 233: Subscriber wireless terminal 24: Subscriber line (metal cable) 25: Radio base station 26: Radio base station radio Frame 261: Transmission time slot 262: Reception time slot 263: Control channel time slot (Time slot 1) 27: Subscriber wireless terminal antenna 28: Wireless cell (radio base station radio wave arrival area) 29: Maintenance terminal device 301: Broadcast audio input microphone 303: Microphone amplifier unit 305: Adder 307: Private exchange interface unit 311: Emergency broadcast instruction switch 310: Broadcast instruction switch group 312: Group broadcast switches # 1, # 2 314: Broadcast end switch 315: switch determination unit 317: PB signal Generator 319: Power supply 321: Broadcast instruction switch 402: Broadcast controller interface 404: PCM codec 406: Wireless base station interface 407: Maintenance terminal interface 408: CPU 409: Address / data bus 414: Storage device Section 415: Selector section 502: B1-channel LD-CELP codec section 504: Multiplexing section 506: Selector section 508: Line interface section 510: OCU 512: LD-CELP codec section for B1 channel normal call 516: B1 channel for normal call ADPCM codec section 519: LAPD controller section 521: B4 channel ADPCM codec section for normal communication 524: Dual port RAM 525: Wireless base station interface section address Data bus 702: Wireless section 703: Control line 705: TDMA controller section 707: Line interface section 708: LAPD controller section 711: DSU 716: Power supply section 718: Address data bus 802: Wireless section 805: TDMA controller section 809: For broadcasting LD-CELP codec section 810: LD-CELP codec section for normal communication 811: ADPCM codec section for normal communication 814: Selector section 817,818: PCM codec section 821: Speaker interface section 822: Telephone interface section 827: Serial interface 828: CPU 830: Address / data bus 831: ROM (electrically rewritable storage device) 832: RAM 1001: Wireless base station TDMA frame 1 02: TDMA frame for subscriber wireless terminal 1003: Indicates synchronization 1004: Control channel interval (100 msec) 1005: 1 frame (5 msec) 1006: PCH transmission timing for broadcast incoming call 1007: PCH transmission timing for normal call 1008: Radio base Station transmission time slot 1009: Radio base station reception time slot 1010: Subscriber radio terminal reception time slot 1011: Subscriber radio terminal transmission time slot 1012: Broadcast incoming call PCH reception timing 1013: Normal call call PCH reception timing 111: Broadcast number 112: Call path 113: Physical interface between private exchange and wireless base station 114: Physical interface between wireless base station and subscriber wireless terminal 115: Broadcast start instruction 116: Broadcast audio 117: B1 channel 118: B1 channel ADPCM coded data in the channel 119: LD-CELP coded data structure in the B1 channel 121: Physical time slot for communication 122: I channel data 123: ADPCM coded data in the I channel data 124: LD- for normal communication in the I channel CELP coded data 125: LD-CELP coded data for broadcasting in I channel 1301: PB signal for broadcast start command 1302: SETUP signal 1303: PCH (broadcast incoming call command) 1304: Timer T1 1305: USCCH (broadcast channel request) 1306: USCCH (broadcast channel allocation) 1307: Timer T2 1308: Synchronous burst 1309: PB for broadcasting end 1310: DISC signal 1311: Wireless channel disconnection 1312: Timer T3 141: PCH format 142: Ich signal Format 1421: Broadcast instruction setting contents 143: PS number 144: Extended paging service type 145: Group number 151: USCCH format 152: Ich signal format 153: Broadcast data content 161: Broadcast call, normal call determination 162: Simultaneous, group broadcast Judgment 163: Self-addressed group broadcast judgment 164: Broadcast reception processing 165: Normal call processing 166: Emergency / simultaneous broadcast judgment 167: Speaker output maximum volume setting

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04M 3/00 H04Q 3/58 101 5K067 3/42 102 H04B 7/26 109A H04Q 3/58 101 H04L 11 / 02 E (72) Inventor Atsuhiko Sato 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside Hitachi, Ltd.Communication Systems Division (72) Inventor Shigeyuki Ejiri 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Hitachi, Ltd. MHIAKI Ueda, Inventor Michiaki Ueda 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture F-term (reference) 5K015 AA00 AA02 AB00 AF05 CA00 CA02 5K028 AA08 BB06 CC05 DD01 DD02 HH02 LL02 MM12 MM13 5K030 GA08 HB01 HB11 HC13 JA13 JL01 JL08 JT01 LD07 5K049 A A08 BB04 BB09 BB19 CC04 DD04 FF01 FF51 GG00 JJ01 JJ02 KK02 KK14 5K051 AA05 BB01 CC01 DD03 DD11 DD15 EE04 FF02 FF11 GG00 HH01 HH02 HH12 HH13 HH26 JJ05 JJ09 JJ11 BB12 DD13 BB12 DD02

Claims (7)

[Claims] 1. A broadcast control device for inputting a broadcast type and an audio signal to be broadcast to a private exchange, a plurality of radio base stations wired to the private exchange, and a radio base station installed in a radio range of the radio base station. A plurality of subscriber radio terminals, wherein the radio base station and the subscriber radio terminals transmit one frame with the number of target slots of n (integer) time slots and n downlink time slots. And means for performing location registration, incoming call, outgoing call control by the control information channel, using time slots other than the above, and communicating telephone communication and broadcast audio signal communication in a wireless TDMA system, The subscriber wireless terminal has a broadcast communication path for reproducing an encoded signal of the broadcast audio signal and a telephone communication path for encoding and decoding the audio of the telephone. Transmission function with a wireless communication system. 2. The wireless communication system according to claim 1, wherein said broadcast control device has a PB signal generating means corresponding to a broadcast instruction and a broadcast type, and said private exchange exchanges a first audio signal for encoding said broadcast audio signal. , A second encoding unit for encoding the encoded signal of the first codec unit and the telephone call signal, and a signal format for transmitting the signal of the second encoding unit to the radio base station And a signal processing unit for detecting the PB signal and controlling the radio base station interface unit. The radio base station receives a broadcast instruction from the broadcast control device, and controls the radio base station. A means for transmitting a broadcast call request signal to the subscriber wireless terminal by a channel, wherein the subscriber wireless terminal has means for responding to the broadcast call request signal; Communication system. 3. The third encoding section for encoding the encoded signal of the first codec section into a lower-speed encoded signal, the second encoding section encoding the telephone call signal by the third encoding section. A fourth encoding unit that encodes an encoded signal having the same speed as the encoded signal of the third encoding unit, and a telephone call signal encoded by the fourth encoding unit that is encoded by the fourth encoding unit. A fifth encoding unit that encodes into a code faster than the speed of the encoding unit;
And a multiplexing unit for multiplexing the coded signal of the fourth coding unit, and the signal processing unit for controlling the radio base station interface unit uses the TDMA slot for the speech call by the radio base station. 3. The radio with a broadcast function according to claim 2, further comprising a processing unit that selects one of the output of the multiplexing unit and the output of the fifth encoding unit according to a state and generates a transmission signal to the radio base station. Communications system. 4. The wireless communication system with a broadcast function according to claim 1, wherein said subscriber wireless terminal has means for connecting at least one of an analog fixed telephone and a personal computer. 5. A method for constructing a wireless communication system with a broadcasting function according to claim 1, wherein said private exchange and said plurality of wireless base stations are connected by wire. A method for constructing a wireless communication system with a broadcast function, comprising using a pair cable used in a wired telephone system. 6. One of the broadcast types broadcasts in a specific group unit of the plurality of subscriber wireless terminals,
The wireless communication system with a broadcast function according to any one of claims 1 to 4, further comprising means for performing a broadcast in a group unit by assigning a number to a group unit of the private exchange and the subscriber wireless terminal. 7. The private branch exchange is connected to the radio base station by an S.
The transmission of an I (start of systematic consultation) frame, the activation of a timer, and the reception of the SI until the acknowledgment signal SQ for the SI frame from within the radio base station is received.
5. The apparatus according to claim 1, further comprising means for retransmitting the frame, counting the number of retransmissions, checking the number of retransmissions that cannot be received in a predetermined period, and judging the quality of the line between the private branch exchange and the radio base station. A wireless communication system with a broadcast function according to item 1.