JPH0448830A - Time division communication method for mobile body communication - Google Patents

Abstract

PURPOSE:To simplify the circuit constitution and to attain economy and miniaturization by deviating a timing of a frame sent from a radio base station and that of a frame sent by a mobile radio equipment by at least one time slot. CONSTITUTION:A signal whose one frame consists of time slots SD1-SDn is fed to a modulation circuit in a radio transmission circuit 32. On the other hand, a signal from a mobile radio equipment 100 sends a reply signal to a radio base station 30 while deviating at least one time slot as the transmission timing to the station 30 after the reception of the signal from the equipment 100. The signal sent from the mobile radio equipment 100 is received by an antenna section of the radio base station 30 and given to a radio reception circuit 35. Thus, even when the transmission signal is invaded to a reception section of its own station, the adverse effect of production of intermodulation is prevented in advance and a transmission or a reception filter is not required, then no insertion loss is caused and miniaturization and economy are attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a time-based glj communication method for a wireless communication channel in mobile communication. More specifically, within each focal line base station that covers multiple zones and constitutes a service area, a certain radio channel is provided, and this is used to select one of the many mobile radios within the service area. When one of the wireless base stations sets up a wireless line and communicates with the opposing wireless base station, the operation of the transmitter and receiver must be adjusted in order to prevent interference even if the transmitter's transmission output mixes with the own receiver. This invention relates to a time division communication method that separates time.

"Prior Art" In mobile communication using voice to which a small zone method is applied, a method employing a time division time compression multiplex signal is described in the following document.

Literature 1. Ito ``Study of mobile phone system - Proposal of time-division time compression FM modulation system - PA IE Technical Report RC389-
11 July 1989 literature 2. Ito “'Study of mobile phone system - theoretical study of time-division time compression FM modulation system’ IEICE technical report RC38
9-39 October 1989 document 3. S, I publication 'A PROPO3AL OF TI
) fE-DVISION, TI) iE-COMPRE
SSED)4ULTIPLEXING FMMOBI
LE RADIOS'/STEM” 40th rE
EE VTGProceedings, PP220
-225) lay 1990 In other words, in Document 1, a transmission signal (baseband signal) is divided into predetermined time intervals and stored in a storage circuit, and when read out, the speed is n times faster than the speed at which it is stored in the storage circuit. It is built into mobile radios and radio base stations in order to be read out in a predetermined time slot at high speed, angle-modulated or amplitude-modulated with the signal accommodated by the time slot, and transmitted and received intermittently over time. a wireless receiving circuit having a receiving mixer that communicates with each other, a wireless transmitting circuit having a transmitting mixer, a synthesizer applying voltage to the receiving mixer of the wireless receiving circuit, and a synthesizer applying voltage to the transmitting mixer of the wireless transmitting circuit. In contrast, a switch circuit is provided to intermittent the output of each applied synthesizer, and to synchronize this intermittent state for both transmission and reception, and to synchronize the same intermittent transmission and reception as above to the radio base station communicating with the mobile radio. In order to extract only the signal accommodated in the predetermined time slot, the receiving side opens and closes the radio receiving circuit to receive the signal, demodulates the signal, and stores the obtained signal in the storage circuit. An example of a system has been reported in which a system is constructed in which it is possible to reproduce the baseband signal, which is the original signal that has been transmitted, by reading it out at a low speed that is 1/n of the speed at which it is stored in this memory circuit. ing.

Next, Document 2 describes the above-mentioned time division time compression multiplexing (
Adjacent channel interference and co-channel interference, which are problems when applying the TCM>FM method to small zones, are being studied, and a system that eliminates these problems can be realized by appropriately selecting system parameters. The possibility of

Furthermore, in addition to the various problems when applying the TCM-FM method to small zones as mentioned above, Document 3 also introduces a new concept of the number of repeated time slots, instead of the concept of the number of repeated zones, which is a problem in the small zone method. This paper proposes a concept and shows an example of system construction for this case.

1. Problems to be Solved by the Invention] However, in the conventional system construction example, the moving heat I! Depending on the operation of the machine, conventional SCPC (Singl.
Similar to systems that use transmitters and receivers continuously and simultaneously, such as the e-Channel Per Carrier system, there is a possibility that intermodulation may occur due to the transmission output mixed into the receiving section of the mobile radio device itself. Measures were needed to prevent this.

Therefore, although there is a way to simplify and make the equipment configuration more economical by taking advantage of the time division compression transmitter/receiver, which is a feature of TCM (time division time compression multiplexing), no concrete measures have been made. There was an issue that needed to be solved.

[Means for solving problem 1] Time division time compression multiplexing (T
CM > Within the time slot within one frame in which the signal is transmitted (in this case, there should be no signal transmitted from the wireless base station to the mobile radio, and the signal is transmitted within the time when no transmitted signal exists) In order to make it possible to receive the signals transmitted by the mobile radio, by shifting the time timing of the frame transmitted by the radio base station and the frame transmitted by the mobile radio by at least one time slot, the transmission signal transmitted by the mobile radio It is possible to remove the bandpass filter that was conventionally inserted on the output side of the transmitter and the input side of the receiver, and it is possible to simplify the circuit configuration and make it more economical and compact. And so.

[Function] In order to prevent the transmitting output of the mobile radio device in the conventional system from entering the receiving section, a circulator is installed at the antenna input end, and a desired frequency is connected to the transmitter output side and the receiver input side. A bandpass filter with steep filtering characteristics for transmitting or receiving only signals is inserted. As a result, insertion loss occurs, and extra transmission power is required to compensate for the insertion loss in the transmission output, and the C/N (carrier radiation and noise ratio) of the receiver deteriorates by the amount of insertion loss. Therefore, a commensurately large transmission power is required for opposing communication. T.C.
The same situation applies to M-FM unless special measures are taken. However, by shifting the time timing of the above-mentioned transmission and reception, it is possible to prevent the transmission output signal from entering the receiving receiver.
It has become possible to reduce the transmission power, simplify the circuit, and provide an economical system.

Embodiment FIGS. 1A, 1B, and 1C show a system configuration for explaining an embodiment of the present invention.

In FIG. 1A, 10 is a general telephone network, and 20 is a gateway exchange for connecting the telephone network 10 and a wireless system. 30 is a wireless base station and a barrier exchange 112
0, a circuit for converting the signal speed, a circuit for allocating and selecting time slots, a control unit, etc. 100-n) and a wireless transmitting/receiving circuit for transmitting and receiving wireless signals.

Here, between the barrier switch 20 and the wireless base station 30,
There are transmission lines for transmitting communication signals 22-1 to 22-m including communication signals of communication channels C)-11 to CHn and control signals.

FIG. 1B shows a circuit configuration of mobile radio device 100 that communicates with radio base stations 30-1 to 30-n. Received signals such as control signals and call signals received by the antenna section enter a radio reception circuit 135 that includes a reception mixer 136 and a reception section 137, and the communication signal that is the output thereof is sent to a speed recovery circuit 138 and a clock regenerator 141. The signal is input to the reception quality monitoring section 158. In the clock regenerator 141,
A clock is recovered from the received signal and transmitted to the speed recovery circuit 138, control unit 140, and timing generator 142.
is applied to the speed conversion circuit 131.

The speed restoration circuit 138 restores the speed (pitch in the case of an analog signal) of each compressed and separated communication signal in one time slot in the received signal of one channel to generate a continuous signal. obtained,
It is input to the telephone unit 101 and the control unit 140.

The communication signal output from the telephone unit 101 is divided into predetermined time intervals by a speed conversion circuit 131, and the speed (pitch in the case of an analog signal) is made high (compressed) and sent to a transmission mixer 133. The signal is applied to the wireless transmission circuit 132 including the section 134. The timing at which this signal is applied is delayed by one time slot or more after receiving the signal from the wireless base station 30, as will be described later. This transmission signal is then sent out from the antenna section using one time slot and received by a plurality of radio base stations 30.

A reception quality monitoring section 158 to which a portion of the output of the reception section 137 is applied monitors the reception quality (signal-to-noise ratio and presence or absence of interference) of the input signal. Further, an interference detector 162 is connected to the antenna receiving end in parallel with the input to the receiving mixer 136,
This is used to detect interference with one's own communication on the same channel and same time slot used for other communications, either in other systems or within the same system. This interference detector 162 monitors the presence or absence of interference during communication, and if it detects interference exceeding a certain level, it reports it to the control unit 140.

The timing generator 142 uses the clocks from the 14 clock regenerators and the control signals from the controller 140 to control the transmission/reception intermittent controllers 123. The speed conversion circuit 131 supplies necessary timing to the speed restoration circuit 138.

This mobile radio 100 includes synthesizers 121-1 and 1 to enable transmission and reception of roughly one channel.
21-3, selector switch 122-1.122-2,
It includes a transmission/reception intermittent controller 123 that generates signals for switching the changeover switches 122-1 and 122-2, respectively, and includes synthesizers 121-1 and 121-3, a transmission/reception intermittent controller 23, and a timing generator 142. is controlled by the control section 140. Each synthesizer 121 and 121-3 includes a reference crystal oscillator 120.
The reference frequency is supplied from With such a configuration, it is possible to communicate with the wireless base station 30 using one channel.

A wireless base station 30 is shown in FIG. 1C.

Communication signal 22-1 of open m channel with gateway exchange 20
22-m are connected to the signal processing section 31 forming an interface through a transmission path.

Now, the communication signal 22- sent from the barrier switch 20
1 to 22-m are input to the signal processing unit 31 of the wireless base station 30. The signal processing section 31 is equipped with an amplifier for compensating for transmission loss, and also performs so-called 2-wire to 4-wire conversion. That is, the input signal and the output signal are mixed and separated, and the input signal from the barrier switch 20 is sent to the signal speed conversion circuit group 51.

Further, the output signal from the signal speed restoration circuit group 38 is transmitted to the barrier exchange 20 as communication signals 22-1 to 22-m by the signal processing unit 31 using the same transmission path as the input signal.

Among the above, the input signal from the barrier switch 20 is input to the signal speed conversion circuit group 51 including many signal speed conversion circuits 51-1 to 5-m, and is divided into speeds (pitch) at predetermined time intervals. receive.

In addition, the signal transmitted from the wireless base station 30 to the barrier exchange 1120 is such that the output of the wireless receiving circuit 35 is
The signal is inputted to the signal speed restoration circuit group 38 via the signal speed recovery circuit group 9 and subjected to speed (pitch) conversion, and then inputted to the signal processing section 31 through the switch group 83.

Now, the control of the radio reception circuit 35 or the output of the call signal is carried out by the signal selection circuit 3 which selects signals for each time slot.
The signal is input to a signal selection circuit group 39 including 9-1 to 39-m, where the speech signal is separated corresponding to each speech channel, CH1 to CHm.

After this output is restored to a signal speed (pitch) by a signal speed restoration circuit group 38 including signal speed restoration circuits 38-1 to 38-m provided corresponding to each call signal, the output is processed by a signal processing unit. 31 and undergoes 4-wire to 2-wire conversion, the output is sent to the barrier switch 20 as communication signals 22-1 to 22-m.

The transmission quality monitoring section 34 has the functions of both the reception quality monitoring section 158 and the interference detection section 162 of the mobile radio device 100,
When deterioration in reception quality or interference is detected, the control unit 40
will be reported to.

Further, the signal processing section 31 has a function of allowing two channels to be used simultaneously for the designated mobile radio device 100 according to instructions from the control section 40. This is used for simultaneous communication using different radio channels within the same zone during communication, or for simultaneous communication using different time slots of the same channel, and is used for simultaneous communication using different radio channels within the same zone.
This is a function used to enable communication in slots).

Here, the specific configuration of each radio receiving circuit 35 is as follows.
This is the same as the radio receiving circuit 135 of the mobile radio 8!100 shown in the figure.

Next, the functions of the signal speed conversion circuit group 51 will be explained.

By storing input signals such as audio signals and control signals divided into a certain length of time in a storage circuit, and changing the speed when reading them out, for example, reading them out at a speed 15 times faster than when they were stored, the signal can be read out. It becomes possible to compress the time length. The principle of the signal speed conversion circuit u51 is the same as when playing back audio recorded by a tape recorder at high speed.
argeCoupled Device), BB
D (Bucket BrigadeDeViCe)
It is possible to use the memory used in television receivers and tape recorders that compress or expand the time axis of conversations (Reference: Koita
Others “'Tape recorder that compresses/expands the time axis of conversation’ Nikkei Electronics July 26, 1976
92-133).

The circuit using COD or BBD exemplified in the signal speed conversion circuit group 51 can be used as it is in the signal speed restoration circuit group 38 as described in the above-mentioned literature. This can be achieved by making the reading speed slower than the writing speed by receiving a timing signal from a timing generation circuit 42 that generates timing using the clock and a control signal from the control section 40.

Control or call signals output from the barrier switch 20 via the signal processing section 31 are input to the signal speed conversion circuit group 51, where speed (pitch) conversion processing is performed and the signals are converted into signals for each time slot. Signal assignment circuit group 52 to be assigned
is applied to The signal allocation circuit group 52 is a buffer memory circuit that stores each section of high-speed signals output from the signal speed conversion circuit group 51, and outputs signals to the timing generation circuit 42 according to instructions from the control section 40.
The signal in the buffer memory is read out using the timing information from and transmitted to the wireless transmission circuit 32. This timing information is arranged in series without overlapping in chronological order when viewed in response to call signals, and if the control signal or control signal and call signal described later are all implemented, it will appear as if it were a continuous signal wave. become that way.

The state of this compressed signal is shown in FIG. 2A and will be explained.

The output signal of the signal speed conversion circuit group 51 is sent to the signal assignment circuit group 5.
2 and are given time slots in a predetermined order. SDl and SD2 in Figure 2A (a)
．． -, SDn indicate that the speed-converted communication signals are allocated to each time slot at the output of the wireless transmission circuits 32-1, 32-2 (simply shown as 32).

Here, one time slot accommodates a synchronization signal and a speech signal or/and control signal as shown in the figure. If the call signal is not implemented, only the synchronization signal is added and the empty slot signal is added to the call signal portion.

In this case, in order to avoid causing radio interference to communications using the same radio channel and the same time thrower in the service zone of another radio base station 30 in the same system, empty time slots are The signals contained in the slot length are only included in the first part of each slot length (e.g., the total 5
%), and for the rest, no radio waves are transmitted at all, and such an embodiment will be described later.

In this way, as shown in FIG. 2A (a), in the wireless transmission circuit 32, the time slots SD1 to SD
Signals forming one frame with n are applied to the modulation circuit. Note that in Figures 2A (a) and (b), the time slots are adjacent to each other, and although it is written that there is no guard time, 5 to 10% of the time slots
A guard time is provided and is omitted from the drawing.

The time-series multiplexed signal to be transmitted is angularly modulated in the radio transmission circuit 32, and then sent out into space from the antenna section.

When making or receiving a telephone call, the wireless base station 30
Regarding the transmission of control signals between the mobile radio device 100 and the mobile radio device 100, it is possible to use either within the telephone signal band or outside the telephone signal band.

Figure 3A shows these frequency relationships. In other words, the figure (a>) is an example of an out-of-band signal, and as shown in the figure, there is a signal on the low frequency side (250Hz>
can be used. This signal is used, for example, when it is desired to send a control signal during a call.

FIG. 3A (b) shows an example of an in-band signal, which is used when making and receiving calls.

Although the above examples were all tone signals, it is possible to transmit many types of signals at high speed by increasing the number of tone signals or by modulating the tone and making it into a subcarrier signal.

The above was a case of analog signals, but if a digital data signal is used as a control signal, it is also possible to digitally encode the audio signal and time-division multiplex the two to transmit. The circuit configuration of is shown in FIG. 3C. FIG. 3C shows an audio signal digital encoding circuit 9.
This is an example of a case in which the data signal is digitized at 1, multiplexed with a data signal by a multiplex conversion circuit 92, and applied to a modulation circuit included in the wireless transmission circuit 32.

Then, it is received by the opposite receiver, and the 3rd C
By performing the operation opposite to that shown in the figure, it is possible to extract the audio signal and the control signal separately.

On the other hand, the mobile radio device 100 receives the signal transmitted from the radio base station 30 and transmits a response signal to the radio base station 30, and the timing of this transmission is shown in FIG. 2A (b). Like moving inorganic machine 10
At least one time slot (
To be exact, the transmission is shifted by a time (indicated by τ in FIG. 2A(b)), which is the sum of one time slot and the guard time. It will be explained below that this time delay amount τ can be ignored.

According to References 1 to 3, in a normal TCM-FM system, the time of one frame is 1 to several tens of m5ec,
This includes 10 to 1000 time slots. Therefore, the length of one time slot is 1 μs
It will be about ec~1m5ec. Therefore, even if other factors such as a filter are added, the delay time can be kept within several milliseconds, and if it is within this range, it will not have a major effect on communications, such as telephone calls.

The signal sent from the mobile radio device 100 having the delay amount τ as described above is received by the antenna section of the radio base station 30 and input to the radio reception circuit 35. Figure 2A (b)
is a schematic representation of this upstream input signal.

That is, time slots SUI, 5LI2 . −． 5
LIn is the mobile radio device 100-1, 100-2. −． 1
A transmission signal addressed to the wireless base station 30 from 00-n is shown. Also, each time slot 5tJ1. SU2. ..., su
If the contents of n are shown in detail, as shown in the lower part of FIG. 2A (b), it consists of a synchronization signal and a call signal or/and a control signal. However, depending on the short distance between the radio base station 30 and the mobile radio 11i100 or the signal speed, it is possible to omit the synchronization signal.

Among the input signals arriving at the wireless base station 30, the control signal is immediately transmitted from the wireless receiving circuit 35 to the control unit 40.
added to. However, depending on the magnitude of the speed conversion rate, it is also possible to apply the output of the signal speed restoration circuit group 38 to the control unit 40 after performing similar processing on the call signal. Further, the call signal is applied to the signal selection circuit group 39.

A timing signal from a timing generation circuit 42 that generates a predetermined timing is applied to the signal selection circuit group 39 in accordance with a control signal instruction from the control unit 40, and a synchronization signal is generated for each time slot 5LJ1 to Sun. The signal or (and) control signal is output separately. Each of these signals is input to a signal speed restoration circuit group 38. This circuit has a function of performing inverse conversion of the speed conversion circuit 131 (FIG. 1B) in the mobile radio device 100 on the transmitting side.
As a result, the original signal is faithfully reproduced and transmitted to the gateway exchange 20.

The manner in which signals are transmitted in the signal space according to the present invention will be explained below using the required transmission band and the relationship between this and adjacent wireless channels.

As shown in FIG. 1C, the control signal from the control unit 40 is sent to the wireless transmitter circuit 32 in parallel with the output of the signal υ1 of the circuit group 52.
added to. However, depending on the size of the speed conversion rate, the signal allocation circuit group 52
It is also possible to add the output to the wireless transmission circuit 32.

Even if the mobile radio device is located 1.00 km away, as shown in FIG. 1B, the circuit configuration is required when the communication path is one channel among the functions of the radio base station 30.

Original signal, for example, an audio signal (0.3kH2 to 3.0kH2
) or the signal speed conversion circuit group 51 (FIG. 1C), the frequency distribution on the output side is shown in FIG. 3B. In other words, if the audio signal is converted 15 times as described above, the frequency distribution of the signal is as shown in Figure 3B < 4
．． 5kHz2~45k)-1z. The figure shows a case where the control signals are simultaneously transmitted using the lower frequency band of the audio signal. It is assumed that among these signals, a control signal (0.2 to 4.0 kHz) and a speech signal CH1 (expressed as SDI at L5 to 45 kHz) are accommodated in a time slot, for example, SDI. Other time slots SD2 to SD
The same applies to the audio signal contained in n.

That is, time slot sD;r;=2°3,-,
n) k: H control signal @ (0,:?~4.Ok H
z> and a communication signal CHi(4,5-45k)-1z) are accommodated. However, the signals in each time slot are arranged in chronological order, and the signals in multiple time slots are not applied to the wireless transmission circuit 32 at the same time.

These call signals are sent to the wireless transmission circuit 32 along with control signals.
When added to the angle modulator included in the angular modulator, the required transmission band requires at least fo±45 kHz. However, fC is the radio carrier frequency. If there are a plurality of wireless channels given to the system, the speed-up of the signal by the signal speed conversion circuit group 51 is limited to a certain value due to the limitations on these frequency intervals. The frequency interval of multiple wireless channels is f
rep and the maximum signal speed due to the above-mentioned audio signal speed increase is f. Then, the following inequality must hold between the two.

f > 2 f H ep On the other hand, in digital signals, audio is usually digitized at a speed of about 64 kb/s, so read by raising the scale on the horizontal axis in Figure 3B, which explains the case of analog signals, by about one digit. Although necessary, the relationship in the above equation also holds true in this case.

Further, the control signal input from the mobile radio device 100 to the radio base station 30 is input to the radio reception circuit 35, but a part of the output is input to the control unit 40, and the other part is input to the signal selection circuit group 39. The signal is sent to the signal speed restoration circuit group 38 via the signal speed restoration circuit group 38. After the latter control signal undergoes a speed conversion (conversion to a low speed signal) that is completely opposite to that at the time of transmission, it becomes the same signal speed as that used in the general telephone network 10 and is transmitted via the signal processing section 31. It is sent to the barrier exchange 20.

Next, the call originating/receiving operation of the system according to the present invention will be explained by taking the case of a voice signal as an example.

(1) Call origination from mobile radio device 100 This will be explained using the flowcharts shown in FIGS. 4A and 4B.

When the mobile radio device 100 is powered on, the first
In the wireless receiving circuit 135 in Figure B, the downlink (wireless base station 30
→Mobile radio device 100) Start capturing the control signal included in the radio channel (channel CH1). If the system is provided with multiple radio channels, i) the radio channel exhibiting a received input electric field of R;
) A radio channel indicated by a control signal included in the radio channel; i) A radio channel ( It enters the receiving state for channel CH1 (hereinafter referred to as channel CH1). This is possible by capturing the synchronization signal within the time slot SDi shown in FIG. 2A(a). In the control unit 140, the synthesizer 121-
A control signal is sent to the synthesizer 122-1 to generate a local frequency that enables the reception of the radio channel C)-11, and the switch 122-1 is also fixed in the position of the synthesizer 121-1.

Therefore, when the receiver of the telephone section 101 is turned on-hook (starts making a call) (3201, FIG. 4A), the synthesizer 121-3 of FIG. 1B generates a local frequency that enables transmission of the wireless channel CHI. A control signal is received from the control section 140 to cause the control to occur.

In addition, the switch 122-2 is also turned to the synthesizer 1213 side and becomes fixed. Next, wireless channel C) 11
The call control signal outputted from the telephone unit 101 is sent using the telephone unit 101. This control signal uses the frequency band shown in FIG. 3A (b) and is transmitted using, for example, time slot Sun.

The transmission of this control signal is limited to time slot Sun, and is sent in bursts, and no signal is transmitted during other time slots (Sun), so there is no negative effect on other communications.However, the speed of the control signal is If the speed of the signal is slow or the amount of information in the signal is too large to be accommodated in one time slot, the signal is transmitted one frame later or further using the same time slot in the next frame. .

Specifically, the following method is used to capture the time slot Sun. The control signal transmitted from the radio base station 30 includes a synchronization signal and a subsequent control signal, as shown in FIG. Synchronization becomes possible.

Roughly speaking, this control signal includes control information such as currently used time slots and unused time slots (empty time slot display). Depending on the system, the time slot so; <r=1.2°...,
n) may contain only synchronization and speech signals when used by other communications; however, even in such cases, unused time slots usually contain synchronization and control signals. By receiving this control signal, it is possible to know which time slot the pre-move II device 100 should use to send out the calling signal.

Note that if all time slots are in use,
It is not possible to make a call on this radio channel and it is necessary to sweep and search for another radio channel.

In other systems, there may be no empty slot indication within any of the time slots, in which case the audio multiplex MSDI that follows.

It is necessary to search for the presence or absence of SC2, . . . , SDn one after another and check for empty time slots.

Now, returning to the main topic, the mobile radio device 100, which has received the control information sent from the radio base station 30 by one of the above methods, determines in which time slot it should send the call control signal. It is possible to make a judgment including the transmission timing.

Therefore, assuming that the time slot Sun for uplink signals is an empty slot, it is decided to use this empty time slot, and the necessary timing is determined from the response signal from the radio base station 30 by sending out a control signal for calling. burst-like control signals can be sent out.

If there is a call from another mobile radio at the same time, the calling signal will not be properly transmitted to the radio base station 30 due to call collision, and the operation will have to be restarted from the beginning, but this probability is When viewed as a system, this value is kept to a sufficiently small value. If call collisions are to be further reduced, the following method may be used. If the mobile radio 11100 finds an empty time slot in which it can make a call, it does not use the entire time slot, but uses only the first half for some mobile radios and the second half for others. This is the way to do it. In other words, the portion of the time slot used as a calling signal is divided into several types, and this is used to classify a large number of mobile radios into groups, and each group is assigned a time period within that one time slot. It is a way of giving. Another method is to create many types of frequencies for control signals, group a large number of mobile radios, and give these to each group. According to this method, even if frequency control signals are transmitted simultaneously using the same time slot, no interference will occur at the radio base station 30. The above two methods may be used separately, or if the two methods are used in combination, the effect will increase synergistically.

Now, suppose that the call control signal from the mobile radio device 100 is successfully received by the radio base station 30 and the ID (identification number) of the mobile radio device 100 is detected (S202). Search for time slots. The time slot given to the mobile radio device 100 may be Sun, but a search is performed just to be sure. It is mobile radio 1
In addition to 00, this is also used to accommodate simultaneous calls from mobile radios, and to provide time slots suitable for service types and service classifications.

As a result, for example, if time slot SD1 is vacant, time slot SD1 of radio channel CH1 is used for mobile radio 11100, and time slot uplink (mobile radio 100→radio base station 30) is performed by a downlink control signal. SUI.

and the corresponding downlink (radio base station 30→mobile radio device 100>instruction to use SDI (320
3>. In response, the mobile radio device 100 transitions to a state in which it can receive data in the instructed time slot SD1, and also transfers the time slot 5U1 (second A
(see figure (b)). However, the transmission timing of this time slot is delayed by at least one time slot, as shown as τ in FIG. 2A.

At this time, in the control unit 140 of the mobile radio device 100,
The transmission/reception intermittent controller 123 is operated, and the switch 122-
1 and 122-2 to start operating (S204>. At the same time, a slot switching completion report is sent to the wireless base 830 using uplink time slot SU1.5205>
, wait for dial tone (8206>).

In addition to the time slot SU1, the radio base 830 receives uplink signals SU3 and Sun included in one frame from another mobile radio m1oo.

The radio base station 30 that has received the slot switching completion report (
5207 >, sends a calling signal to the gateway exchange 20 3208 >, upon receiving this calling signal, the gateway exchange 20 detects the ID of the mobile radio 100 and selects one of the switches included in the gateway exchange 20. Turn on the necessary switches (S209>, and send out a dial tone (3210)
, Figure 4B).

This dial tone is transferred by the radio base station 30 (5211>), and the mobile radio m1oo confirms that the communication path has been set up (3212).

When transitioning to this state, telephone unit 1 of mobile radio m1oo
Since a dial tone is heard from the 01 handset, the dial signal begins to be sent. This dial signal is speed-converted by the speed conversion circuit 131 and sent out from the wireless transmission circuit 132 including the transmission section 134 and the transmission mixer 133 using the upstream time slot SU1 (3213>).

Thus, the transmitted dial signal is received by the radio receiving circuit 35 of the radio base station 30. This radio base station 30 has already responded to the calling signal from the mobile radio 100,
In addition to giving the time slot to be used, the signal selection circuit group 39 and the signal allocation circuit group 5 of the wireless base 830
2, the upstream time slot SU1 is received, and the downstream time slot SD1 signal is transmitted.

Therefore, the dial signal transmitted from the mobile radio 11100 is transmitted to the signal selection circuit 39- of the signal selection circuit group 39.
1, the signal is input to the signal speed restoration circuit group 3B, where the original transmission signal is restored, and transferred to the gateway exchange 20 as a call signal 22-1 via the signal processing section 31 (S2
14), a call path to the telephone network 10 is set (S215
>.

On the other hand, an input signal from the barrier switch 20 (initial control signal,
When a call is started, the call signal is subjected to speed conversion in a signal speed conversion circuit group 51 in the radio base station 30 and then is given to a signal allocation circuit group in a signal allocation circuit group 52. Then, it is transmitted from the radio transmission circuit 32 to the mobile radio device 100 using the time slot 501 of the downlink radio channel. In the mobile radio 1100, time slot 501 of radio channel C)-11
is on standby for reception and is received by the radio reception circuit 135, the output of which is input to the speed restoration circuit 138. In this circuit, the original signal of transmission is restored, and the telephone unit 101
input into the handset. Thus, a call is started in the dark between the mobile radio device 100 and a regular telephone within the regular telephone network 10 (S216>).

The call is terminated by turning on and knocking on the receiver of the telephone f! The signal is sent from the circuit 132 to the wireless base station 30 (S218>, and the control unit 1
At 40, the operation of the transmission/reception intermittent controller 123 is stopped;
In addition, switches 122-1 and 122-2 are fixed to the output ends of synthesizers 121-1 and 121-3, respectively.

On the other hand, in the control unit 40 of the radio base station 30, the mobile radio device 1
When the call termination signal from 00 is received, the call termination signal is transferred to the barrier exchange 1120 (3219>), and the switch group (not shown) is turned off to terminate the call (3220>).

At the same time, the signal selection circuit group 39 and signal allocation circuit group 52 in the radio base station 30 are opened.

In the above explanation, control signals are exchanged between the radio base station 30 and the mobile radio device 100 by the signal rate conversion circuit group 51. Although it was explained that the signal speed restoration circuit group 38 etc. are not passed through,
This is for the convenience of explanation, and communication can be actually carried out without any problem even through the signal speed conversion circuit group 51, signal speed restoration circuit group 38, control signal speed conversion circuit 48, and signal processing section 31, as with audio signals. be.

In addition, in the call described above, the wireless base station 30
．． Mobile radio 1fil 00 and the time used for communication.
Although the case where each slot is addressed to one slot is described above, the same applies even if a plurality of slots are used. That is, as shown in FIG. 2B, the mobile radio device 100 receives a signal from the radio base station 30-1 using the time slots SDI and SD3, and from the radio base station JN30=2 using the time slot SDp. Upon receiving the signal, mobile radio 100 receives time slot 5L11 . Wireless base station 301 using SU3
to the wireless base station 30 using time slot SUp.
-2, respectively.

The reason why a plurality of time slots are used in this way is to improve signal reception quality through the diversity effect. In addition to the city effect, this is also to facilitate zone switching. Even in such a case, in order to avoid the adverse effects of coupling between the transmitted and received signals that occur in the mobile radio device 100, the transmission timing of the transmission signal from the mobile radio device 100 is adjusted to match the received signal, as shown in FIG. 2B. In comparison, it is assumed that there is a delay of at least one time slot or more, which is the time indicated by τ.

(2) Incoming call to mobile radio device 100 The mobile radio device 100 is on standby with the power turned on. In this case, as explained in the section regarding the call origination from the mobile radio device 100, the mobile radio device 100 is in a waiting state to receive a downlink control signal of the radio channel CH1 in accordance with the procedure defined by the system.

Assume that an incoming call signal to the mobile radio device 100 arrives at the radio base 830 from the general telephone network 10 via the barrier switch 20. These control signals are transmitted as communication signals 22 to the control unit 40 (FIG. 1C) via the signal rate conversion circuit group 51 and the signal allocation circuit group 52, similarly to the voice signals. Then, the control unit 40 uses an empty slot of the downlink time slots of the radio channel CH1 addressed to the mobile radio 100, for example, SDl, to display the ID signal of the mobile radio 1100, the incoming call signal, and the signalman time slot usage signal. (For example, SUl corresponding to SDl is used for transmission from mobile radio device 100).

In the mobile radio device 100 that receives this signal, it is transmitted from the receiving section 137 of the radio receiving circuit 135 to the control section 140. In the control unit 140, this signal is transmitted to the own mobile radio device 10.
The VI recognizes that it is an incoming call signal to 0, so the telephone unit 1
At the same time, the switch 122 operates the transmission/reception intermittent controller 123 to stand by at the designated time slots SD1 and SU1.
-1°122-2 starts turning on and off. In this way, the state has shifted to a state in which calls can be made.

(3) TCM- of the same radio channel in each adjacent zone
Application document 3 of the present invention in the case of using the FM system describes a system construction method in the case of using the same radio channel CM-FM system in each zone constituting the small zone. Application of the present invention to such a system will be described below. Figure 5A is similar to Figure 6 (Reference 3
Now, each wireless base station 30 in the small zone shown in Fig. 4)
This shows the timing of signals sent from. That is, the zone indicated as 1 in FIG. 6 is the zone of the radio base station 30-1 that uses subframe SF1, and the subframe SF
2 is the radio base station 30-2, and the following subframe SF7 is the transmission timing of the transmission signal from the radio base station 30-7.

Now, in order to apply the present invention to a system in which the radio base stations 30 are arranged as shown in FIG. 6, the transmission timing of the mobile radio device 100 shown in FIG. 5B may be used.

That is, in FIG. 5B, wireless base stations 3.0-1.3
0-2. ..., the signal transmission timing from the mobile radio 11100 existing within the service area of 30-7,
For example, time slot 5SD1.5DI-1 (FIG. 5A) of the signal from radio base station 30-1 may be delayed by at least two time slots (indicated by τ2 in FIG. 5B) after being received. Time and time already explained in Figure 2B
The slots SDp and sup are used for communication with adjacent radio base stations 830, and this is only possible if each radio base station 30' has the same radio channel, the same frame configuration, and is temporally synchronized. Become.

It should be noted that even if the mobile radio device 100 moves while communicating between the zones shown in FIG. 6, it is clear that there is no adverse effect on the continuation of communication.

That is, the time slot Sop shown in FIG. 2B,
If SUP is used, and this time slot is used to communicate with the new destination zone each time the user moves to a new zone, there will be no instantaneous communication interruption. In addition, if frame synchronization and slot synchronization are performed through all radio base stations 30, and the signals transmitted from the mobile radio l1100 are also synchronized with this, then multiple radio base stations 30
It is possible to prevent the transmission timing in communication with the radio base station 30 from overlapping with the reception signal from each radio base station 30.

[Effect of the invention] As is clear from the above explanation, the mobile communication system,
In particular, by applying the present invention to the so-called small zone system, in which a service area is configured by covering multiple zones, it is possible to prevent the harmful effects of intermodulation caused by transmitting signals being mixed into the receiving section of the local station. In addition, since it is not necessary to install a transmission or reception filter, there is no insertion loss, and miniaturization and economicalization are possible, so the effects of the present invention are extremely large.

[Brief explanation of drawings]

Fig. 1A is a block diagram showing the connection relationship between the gateway exchange, telephone network, and radio base station in the system of the present invention, Fig. 1B is a circuit block diagram of a mobile radio device used in the system of the present invention, and Fig. 1C 2A and 2B are time slot structure diagrams for explaining time slots used for transmission of time division time compression multiplexed signals. , Figures 3A and 3B are telephone signals. ': A spectral diagram showing the spectrum of the control signal; Figure 3C is a circuit configuration diagram for multiplexing voice signals and data signals; Figures 4A and 4B depict the flow of the calling operation of the system according to the present invention. Flowchart, Figures 5A and 5
Figure B is a time slot structure diagram for explaining the time slots used in transmission 1 of many radio base stations in a small zone configuration, and Figure 6 shows a small zone configuration to which the present invention is applied. FIG. 10... Telephone network 20... Gateway switchboard 22
-1 to 22-n...Communication signal 30...Radio base station 31...Signal processing section 32
... Wireless transmission circuit 34 ... Transmission quality monitoring section 35
...Radio receiving circuit 38...Signal speed restoration circuit group 38-1 to 38-m...Transmission speed restoration circuit 39...
Signal selection circuit group 39-1 to 39-m... Signal selection circuit 40... Control section 41... Clock generator 42... Timing generation circuit 51... Signal speed conversion circuit group 51-1... 51-m...Signal speed conversion circuit 52...
Signal assignment circuit group 52-1 to 52-m...Signal assignment circuit 91...Digital encoding circuit 92...Multiple conversion circuit 100.100-1 to 100-n-...Mobile radio device 10
1...Telephone unit 120...Reference crystal oscillator 1
2t-1, 121-3...Synthesizer 122-1,
122-2...Switch 123...Transmission/reception intermittent controller 131...Speed conversion circuit 132...Wireless transmission circuit 133...Transmission mixer 134...Transmission unit 135
... Radio reception circuit 136 ... Reception mixer 137.
...Receiving section 138...Speed restoration circuit 141.
. . . Clock regenerator 158 . . . Reception quality monitoring unit 162 . . . Interference detector.

Claims (1)

Claims: Each radio base means (30) each covers a plurality of zones and constitutes a service area, and a time base means (30) for moving across the plurality of zones and communicating with the radio base means. Each mobile radio means (100) using a radio channel carrying time-compressed segmented signals in slots.
in a mobile communication system using barrier exchange means (20) for exchanging communications between said mobile radio means, such that time slots used by said mobile radio means for transmitting and receiving do not coincide in time; A time-division communication method for mobile communication using time slots.