JPH03262220A - Time division communication method and system for travelling vehicle communication - Google Patents

Abstract

PURPOSE:To constitute an economical system by sending other signals than a timewise compressed and punctuated signal on a frequency band lower than a frequency band of the timewise compressed and punctuated signal. CONSTITUTION:A signal sent from a radio base station is converted into a prescribed frequency at a reception mixer 136 via an antenna and inputted to a frequency discriminator 212. T he output is demultiplexed by a digital analog signal demultiplexer 213 and a digital signal is sent respectively to an expander 172 and an FDM channel converter 174 vea a band pass filter 214, then no amplifier is required.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a time division communication method and system for a wireless communication channel in mobile communication, and to effective use of multiple load gain of a time compression multiplex signal, which is a modulation signal, in the system. More specifically, given a radio channel, one of the many mobile radios in the service area is communicating with an opposing radio base station by setting up a radio link. When another mobile radio starts communicating with the radio base station in Brazil using the same radio channel, due to the effective use of frequencies or radio wave propagation characteristics, the communication between the mobile radio and the radio At the same time as eliminating any negative effects on communication with the base station, another communication signal is placed in a low frequency band outside the frequency band of the time division multiplexed signal, and the multiple load gain of this signal is also utilized. The purpose of this paper is to provide a method for improving the effective utilization of frequencies by reducing the transmission power, and an economical system using the method.

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

Literature 1. Ito "'Inspection of mobile phone system - Proposal of time-division time compression FM modulation system -" IEICE Technical Report RC389-1
1 July 1989 document 2. Ito ``Study of mobile phone system - Time division time compression F
Theoretical study of M modulation system” IEICE technical report RC389-39
October 1989 In other words, in Document 1, the transmitted 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. built into mobile radios and radio base stations in order to read out signals in predetermined time slots at high speed, angle-modulate or amplitude-modulate carrier waves with the signals accommodated by these time slots, and transmit and receive signals intermittently in time. a radio receiving circuit having receiving mixers facing each other and communicating with each other, a radio 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. A switch circuit is provided for each to intermittent the output of the synthesizer applied to each, and this intermittent state is synchronized for both transmission and reception, and the same intermittent transmission and reception as above is synchronized for the radio base station communicating with the mobile radio. In order to avoid extracting only the signal accommodated in the predetermined time slot on the receiving side, the radio reception circuit is opened and closed to receive the signal, and the signal obtained by demodulation is stored in the storage circuit. However, there is an example of a system in which the baseband signal, which is the original signal that has been transmitted, can be reproduced by reading it out at a low speed that is 1/n of the speed at which it is stored in this memory circuit. It has been reported.

In addition, Reference 2 examines adjacent channel interference and co-channel interference, which are problems when applying the above-mentioned CM (time division time compression multiplexing IFM method) to a small zone, and examines system parameters. It has been shown that the system can be realized by appropriately selecting the following.

Furthermore, the multiple load gain of a so-called frequency division multiplexed signal, which is obtained by converting the frequency of an audio signal and multiplexing it so that it does not overlap on the frequency axis, is described in, for example, the following documents 3 and 4.
is shown.

Literature 3. B, D, Ho1brook, J, T, Di
xon: LoadRating Theory for
r Multichannel Amplifiers
BS Ding J, 18. Oct., 1939 Reference 4.
C, B, Feldman et al.”Band Width a
ndTransmission Performance
e” BSTJ, July 1949490-59
Figure 11 on page 5 was created from Figures 7 of the above-mentioned document 3, and Figure 12 was quoted from page 495 of the above-mentioned document 4, and is substantially the same as that shown in figure 11. This shows that it is possible to obtain the same multiple load gain.

The reason why multiple load gain can be obtained and its application to wireless angle modulation will be briefly explained below.

The level of an active telephone line carrying telephone signals varies from person to person, gender, and subscriber line length; There is always an interval. Also, while the other party is talking, the other party does not speak and no signal is added to one direction. Do not speak during exchange connection. Therefore, the individual signal levels are diverse, and a composite signal of these cannot be easily obtained. However, clarifying this is the most important and fundamental problem in creating a relay line that maintains distortion, crosstalk, quasi-crosstalk, noise, etc. to satisfactory values. Therefore, it has been studied by many people.

FDM method (SS: single 5
The level of the method (method applying ideband) is such a synthesis of voices, the probability that each voice overlaps at the same time is rare, and while the number of communication paths N is small, each voice fluctuates greatly, and the effect on the synthesized signal is Although direct, as the number of multiplexes increases, individual shadows 9 cJ: become less direct and are stochastically averaged. Therefore, the peak value of the composite signal increases very slowly as the number of communication paths increases.

This is B, D, rib brook, J, T, DiXO
n [Reference 3 above] was statistically determined for telephones in the United States. According to the results, the change in power of a sine wave having the same peak value as the peak value of the multiplexed signal is as shown in FIG.

To show how small the increase in the peak value of the multiple telephone signal is, the multiple load gain in FIG. 11 is compared with the sum of the peak voltages of the individual signals. That is, for example 96
In the 0 channel system, 6 channels are loaded at the maximum at the same time, and the peak voltage is the same as when the signal of 954 channels is not loaded.

In the SS-FM system, fluctuations in the voltage of the composite signal result in frequency deviations, so when the peak frequency deviation of the composite signal is set to a certain value and the number of multiplexed communication channels N increases, the voltages of each communication signal are summed. Compared to the multi-load gain shown in Figure 11, the modulation index for each channel can be increased, and the S/
It is improved by that much more than N.

[Problem to be solved by the invention] In the system construction examples shown in the above-mentioned documents 1 and 2,
The existence of a multiple load gain in time-division time compression multiplexed signals transmitted from a radio base station to a large number of mobile radios is not disclosed, and this multiple load gain is not utilized.

Therefore, if an analysis of this multiple load gain had been performed, there would be many benefits that could be gained in system design, namely the increased transmit power level that would be possible by increasing the depth of frequency modulation. Decreasing, TC
Specific advantages such as ease of setting up an amplifier for amplifying the M signal, realization of an economical amplifier by expanding the operating level setting range, and economy by relaxing the rating conditions of mixers, resistors, and capacitors are realized. There was a problem to be solved that could only be done.

What was disclosed in References 3 and 4 clarified the multiple load gain in so-called frequency division multiplexed signals in which audio signals are frequency-converted and multiplexed so that they do not overlap on the frequency axis, and are time-division time multiplexed. It cannot be applied to compressed multiplex (CM) signals, and the existence of multiple load gain is unknown. Wax has many advantages (references 1 and 2 above)
In the case of

Furthermore, in the CM signal, as a result of time-compressing the original signal, an unused low frequency band is generated, and the problem remains as to how to utilize this effectively.

``The means to solve the problem is to take the number of multiplexed TCM (time division time compression multiplexed) signals (number of communication paths), the time length of one room, [■; (the highest frequency of the signal as a parameter), Using the sampling theorem, the multiple load gain of a CM signal was clearly derived in relation to the multiple load gain of an FDM (frequency division multiplexing) signal, and this was made practical.

Furthermore, by using the amplitude distribution characteristics of the CM signal, a compressor (
A compressor) was inserted to change the distribution to the desired distribution, and an expander was installed on the receiver side for demodulation. here,
Since a TCM signal that time-compresses the original signal is used, there will be an unused part in the low frequency band, so in order to make effective use of this part, for example, FDM signals can also be transmitted and received. , FDM channel converters were installed in both the radio base station and the mobile radio.

``Function'' Since it has become clear that multiple load gain exists even in the CM signal, it has become possible to specifically calculate the multiple load gain using various design parameters of the system. By using this together with the multiload gain of the FDM signal, it is possible to gradually reduce the transmission output by deepening the modulation depth of 1M (PM) modulation while keeping interference within the permissible value. The peak value of the output signal from the transmitter no longer increases beyond a certain value in terms of modulation deviation, making it possible to eliminate obstacles to system operation. As a result, it has become easier to design modulators and amplifiers, and the rated values of passive circuits such as mixers, resistors, and capacitors can be lowered, making it possible to construct an economical system.

Embodiment FIG. 1A, FIG. 1B, and FIG. 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 the wireless system. 30 is a wireless base station which interfaces with the barrier exchange 820, a circuit for converting signal speed, a circuit for allocating and selecting time slots,
It has a control section, etc., and in addition to setting and canceling the wireless line,
It has a wireless transmitting and receiving circuit that exchanges wireless signals with the mobile wireless devices 100 (100-1 to 100-n).

Here, between the barrier switch 20 and the wireless base station 30,
There are transmission lines for transmitting communication signals 22-1 to 22n including communication signals of communication channels CH1 to CHn and control signals.

FIG. 1B shows a circuit configuration of a mobile radio device 100 that communicates with a radio base station 30.

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 restoration circuit 138 and a control section 140. It is input to the clock regenerator 141. The clock regenerator 141 regenerates a clock from the received signal and sends it to the speed recovery circuit 13.
B, the control section 140, and the timing generator 142.

The speed recovery circuit 138 calculates the speed (pitch in the case of an analog signal) of the compressed and segmented communication signal in the received signal.
is restored and input as a continuous signal to telephone section 101 and control section 140.

The communication signal output from the telephone unit 101 is divided into predetermined time intervals by the speed conversion circuit 131, and the speed (pitch in the case of an analog signal) is set to high speed (compression), and then sent to the transmission mixer 133. The signal is applied to the wireless transmission circuit 132 including the section 134.

The output of the modulator included in the transmitting section 134 is transmitted to the transmitting mixer 13
3, the signal is converted to a predetermined radio frequency, transmitted from the antenna section, and received by the radio base station 30.

In order for the mobile radio device 100 to send a radio signal to the radio base station 30 using a time slot that is permitted to be used, timing information from the timing generator 142 shown in FIG. 1B is sent to the control unit 14. It is necessary that it is obtained via 0.

In this timing generator 142, the clock regenerator 14
1 and a control signal from the control section 140, the transmission/reception intermittent controller 123. It supplies necessary timing to the speed conversion circuit 131 and speed restoration circuit 138.

This mobile radio device 100 further includes a synthesizer 121.
-1 and 121-2, and selector switches 122-1, 1
22-2, a transmission/reception intermittent controller 123 and a timing generator 142 that generate signals for switching the changeover switches 122-1 and 122-2, respectively.
Synthesizers 121 - 1 and 121 - 2 , transmission/reception intermittent controller 123 , and timing generator 142 are controlled by control section 140 . Each synthesizer 1211.12
1-2 is supplied with a reference frequency from a reference crystal oscillator 120.

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

N-channel communication signal 22-1 with gateway switch 20
22-n are connected to a signal processing unit 31 forming an interface through a transmission path.

Now, the communication signal 22 sent from the barrier switch 20 is -C.
−1 to 22-n are input to the signal processing unit 31 of the wireless base station 30. The signal processing section 3 is equipped with Ij, an amplifier for compensating for transmission loss, and a so-called 2-wire
A 4-wire transformation is performed. That is, the panono signal and the output signal are mixed and separated, and the input signal from the barrier switch 20 is
The signal 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 by the signal processing section 31 using the same transmission path as the input signal. Among the above, the input signal from the barrier exchange If&20 is input to the signal speed conversion circuit group 51 including many signal speed conversion circuits 51-1 to 51-n, and is subjected to speed (pitch) conversion at predetermined time intervals. .

Furthermore, the signal transmitted from the radio base station 30 to the gateway exchange 20 is determined by the output of the radio receiving circuit 35 being transmitted to the signal selection circuit group 39.
is manually input to the signal speed restoration circuit group 3B via
(pitch) is converted and input to the signal @ processing section 31.

5 Now, the control of the radio reception circuit 35 or the output of the call signal is performed by a signal selection circuit 39 that selects a signal for each time slot.
-1 to 39-n is input to the signal selection circuit group 39,
Here, speech signals are separated corresponding to each speech channel CH1 to CHn. This output undergoes signal speed (pitch) restoration in a signal speed restoration circuit group 38 including signal speed restoration circuits 38-1 to 38-n provided for each channel, and then is input to the signal processing section 31. , after undergoing 4-wire to 2-wire conversion, this output is sent to the barrier switch 20 as communication signals 22-1 to 22-2.
2-n.

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 group 51 is the same as when playing back audio recorded by a tape recorder at high speed6, and in reality, for example, CCD (Chargec
(Oewice), BBD (Bu
cket BrigadeDevice) can be used, and the memory used in television receivers and tape recorders that compress or expand the time axis of conversation can be used (Reference M: Kosaka et al. A tape recorder that compresses and expands ' Nikkei Electronics July 26, 1976 92-133
page).

The circuit using a CCD 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 document, and in this case, the circuit using the CCD or BBD as exemplified in the signal speed conversion circuit group 51 can be used as it is in the signal speed restoration circuit group 38. This can be achieved by receiving a timing signal from a timing generator 42 that generates timing based on the clock of 1 and a control signal from the control unit 40, thereby making the reading speed slower than the writing speed.

Control or audio signals outputted from the barrier switch 20 via the signal processing section 31 are manually input to the signal speed conversion circuit group 51, and after speed (pitch) conversion processing is performed, signals are assigned to each time slot. It is applied to the signal allocation circuit group 52. The signal allocation circuit group 52 is a buffer memory circuit that stores one section of high-speed signals output from the signal speed conversion circuit group 51, and receives timing information from the timing generation circuit 42 given by instructions from the control section 40. Then, the signal in the buffer memory is read out and transmitted to the wireless transmission circuit 32. As a result, when viewed in terms of channel correspondence, communication signals are arranged in series without overlapping in chronological order, and when all control signals or communication signals, which will be described later, are implemented, they appear as if they were continuous signal waves. become.

The state of this compressed signal is shown and explained in FIGS. 2A and 2B.

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 in Figure 2A(a), 5D2
-, SDn indicate that the speed-converted communication signals are allocated to each time slot.

Here, a synchronization signal and a control signal or a communication signal are accommodated in one time thrower 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 way, as shown in FIG. 2A(a), the wireless transmitting circuit 3
2, signals forming one frame are applied to the modulation circuit in time slots SD1 to SDn.

The time-series multiplexed signal to be transmitted is angle-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, in the figure (a), it is an example of an out-of-band signal, and as shown in the figure,
Low frequency side (250Hz>) and high frequency side (38501-1z
) 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 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. However, in digital data signals, there is usually no multiple load gain when multiplexing analog signals, which will be described later, so this point must be taken into account when designing the system.

0 and received by the opposing receiver and transmitted to the 3rd C in the demodulation circuit.
By performing the operations opposite to those shown in the figure, it is possible to extract the audio signal and the control signal separately.

On the other hand, the signal sent from the mobile radio device 100 is received by the antenna section of the radio base station 30 and input to the radio reception circuit 35. FIG. 2A (b) schematically shows this upward human input signal.

That is, time slot SU1. SU2. ...S
un is mobile radio 100-1.100-2°...,
100-n shows a transmission signal addressed to the wireless base station 30.

Also, each time thrower 1 to su1. su2,...,s
If the contents of un are shown in detail, as shown in the lower left of FIG. 2A (b), it consists of a synchronization signal and a control signal or/and a telephone call signal.

However, depending on the short distance between the radio base station 30 and the mobile radio device 100 or the signal speed, it is possible to omit the synchronization signal. Further, the waveform of the radio carrier wave of the above-described uplink radio signal within time throwers 1 to 1 is schematically shown in FIG. 2B (C).

Now, among the input signals that have arrived at the wireless base station 30, the control signal is immediately sent to the control unit 40 from the wireless receiving circuit 35.
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 according to a control signal instruction from the control unit 40, and a synchronization signal and a control signal are applied for each time slot 5LII to Sun. The signal or speech signal is separated and output. Each of these signals is
The signal is input to the signal speed restoration circuit group 38. This circuit has the function of inversely converting the speed conversion circuit 131 (FIG. 1B) in the mobile radio device 100 on the transmitting side, thereby faithfully reproducing the original signal and transmitting it to the gateway exchange 20. become.

Hereinafter, the aspect of case 3 in which signal space is transmitted according to the present invention will be explained using the required transmission band and the relationship between this and the adjacent wireless tunnel.

As shown in FIG. 1C, the control signal from the control section 40 is applied to the wireless transmission circuit 32 in parallel with the output of the signal allocation circuit group 52. However, depending on the magnitude of the speed conversion rate, it is also possible to apply the signal to the wireless transmission circuit 32 from the output of the signal allocation circuit group 52 after performing the same processing as the call signal.

Next, as shown in FIG. 1B, the mobile radio device 100 also has a circuit configuration required when the radio base station 30 has one communication channel among its functions. Original signal, for example, audio signal (0.3KH2 to 3.OK+-12)
FIG. 3B shows the frequency distribution on the output side when the signal passes through the signal speed conversion circuit group 51 (FIG. 1C). That is, if the audio signal is converted 15 times as much as described above, the frequency distribution of the signal will be 4. as shown in Figure 3B.
This means that it has been expanded to 5KH2 to 45KHz.

Here, the frequency distribution of the signal has been expanded, but the waveform form has simply been stretched along the frequency axis. It is necessary to note that this is necessary when determining the value of the multiload gain.

Now, FIG. 3B shows a case where the control signal is simultaneously transmitted using the lower frequency band of the audio signal. Of this signal, the control section @(02~4.0KHz >
and call signal CHI (SDl at 4,5~45KH2)
) is a time slot, e.g. S
Suppose that it is housed in DI. Other time slot S
The same applies to the audio signals accommodated in D2 to SDn.

That is, the time slot SD i (i = 2°3, -, n> accommodates the control signal (0,2 to 4.0 KH2) and the communication signal CHi (4,5 to 45 KHz). However, The signals in each time thrower 1 are arranged in chronological order, and signals in multiple time slots are not applied to the wireless transmitter circuit 32 at the same time. It is not implemented when a time slot is provided for the control signal at the beginning of the communication signal, and when the lower frequency band is used for other signals, it is ~4.4kl-
12 or 46-46.5kHz).

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 is at least fo±45 KHz. However, fo is a 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
,. , and let fl be the maximum signal speed due to the speeding up of the audio signal mentioned above, then the following inequality must hold between the two.

f 〉2fH ep On the other hand, in digital signals, the voice is usually 64. k b
Since the signal is digitized at a speed of about /S, it is necessary to raise the scale on the horizontal axis in Figure 3B, which explains the case of an analog signal, by about one digit to read it, but the relationship in the above equation holds true in this case as well. .

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.

1D and 1E, two embodiments 100B and 100C of mobile radio 100 are shown. The difference from the mobile radio device 100 shown in FIG. 1B is that a compression operation is performed to prevent the peak value of the output signal from the transmitter from increasing beyond a certain value in terms of modulation deviation. The main difference is that it is equipped with a compressor 171 to compress the signal, and an expander 172 to expand the signal compressed by the compressor.

In the mobile radio device 100B (FIG. 1D), the compressor 171 includes a speed conversion circuit 131 and a wireless transmission circuit 132.
The expander 172 is provided between the radio reception circuit 135 and the speed restoration circuit 138.

In the mobile radio 100C (FIG. 1F), the compressor 171 is provided between the telephone section 101 and the speed conversion circuit 131, and the expander 172 is provided between the speed restoration circuit 13
8 and a telephone unit 101 is shown.

FIG. 1F shows another embodiment 100D of the mobile radio 100.
It is shown. Mobile radio 100 shown in FIG. 1D
The difference from B is that FDM channel converters 173 and 174 and switches 118-1 and 1182 are added, and these constitute uncompressed signal communication means;
81 selects the received signal from either the FDM channel converter 174 or the speed restoration circuit 138, and the switch 118
-2, by applying the transmission signal to either the FDM channel converter 173 or the speed conversion circuit 131, the signal can be transmitted and received using FDM (frequency division multiplexing) signals or TCM (time division time compression multiplexing). You can choose to send and receive signals.

FIG. 1G shows the radio transmitting circuit 1 shown in FIG. 1F.
Details of a circuit suitable for 32 are shown.

The digital/analog signal mixer 217 includes a control section 14
0, an analog CM signal from the compressor 171, and an FDM channel converter 1.
one of the analog FDM signals from 73,
Three signals are applied and mixed, modulated by a modulator 216, and a transmission output is applied to the antenna section via a transmission mixer 133.

FIG. 1H shows the radio receiving circuit 13 shown in FIG. 1F.
Details of a circuit suitable for 5 are shown.

The received signal from the antenna section is converted into a digital signal via a reception mixer 136° amplifier 2111 and a frequency discriminator 212.
The digital signal is applied to the analog signal separator 213 and is applied to the clock regenerator 141 and the control unit 14 to obtain a digital signal using the timing signal from the timing generator 142.
0, the analog CM signal and FDM signal are passed through a bandpass filter 214 to an expander 172 and FDM signal, respectively.
It is applied to the DM channel converter 174.

Unless otherwise specified below, mobile radio equipment 100.10
0B, 1000, and 100D are collectively referred to as a mobile radio device 100.

Other embodiments 30 and 30C of the radio base station 30 are shown in FIG. 11 and FIG. 1J.

The difference from the radio base station 30 shown in FIG. 1C is that the peak value or modulation deviation of the output signal from the transmitter is compressed to prevent it from increasing beyond a certain value operation] compressor 71 or compressors 71-1 to 71-
n)] and an expander group 72 for conversely expanding a signal compressed by the compressor or expanders 72-1 to 72-n. It is a point.

In the radio base station 30B (FIG. 11), the compressor 71 is provided between the signal allocation circuit group 52 and the radio transmission circuit 32, and the expander 72 is provided between the radio reception circuit 35 and the signal selection circuit group 39. It is provided. In the radio base station 30C (Fig. 1J), the compressor 71-
The repressor group 71 includes signal processors 1 to 71-n.
1 and the signal speed conversion circuit group 51, and the expander group 72 including expanders 72-1 to 72-n is provided between the signal speed restoration circuit group 38 and the signal processing section 31. It is shown.

First, another embodiment 30D of the radio base station 30 is shown in the figure. The difference from the wireless base station 30B shown in FIG. 11 is that FDM channel converters 73 and 74 are added to the transmitting side and the receiving side, and these constitute uncompressed signal communication means. It operates in the same way as the mobile radio device 100D.

Here, switch 11 used in mobile radio device 100D
The functions of B-1 and 118-2 are performed by the signal processing unit 31 in the wireless base station 30D according to instructions from the control unit 40.

1 Below, unless otherwise specified, wireless base station 30.30
B, 300.30D are collectively referred to simply as the wireless base station 30.

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 will be explained using flowcharts 1 through 1 shown in FIGS. 4A and 4B.

When the power of the mobile radio 11100 is turned on, the radio reception circuit 135 in FIG.
0 → mobile radio 100) radio channel (channel CH1
start capturing the control signals contained in the If the system is provided with multiple radio channels, i) the radio channel exhibiting the highest received input electric field);
Wireless channel 11) instructed by a control signal included in the wireless channel; Channel 2 with empty time throwers 1~ among time throwers 1~ in the wireless channel; etc. according to the procedures determined by each system. The wireless channel (hereinafter referred to as channel CH1) is in a receiving state. This is possible by capturing the synchronization signal within time slot SDi, which is illustrated 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 reception of the radio channel CH1, and the switch 122-1 is also fixed in the position of the synthesizer 121-1.

Therefore, when the receiver of the telephone unit 101 is off-hook (starts making a call) (S201, FIG. 4A), the synthesizer 121-2 of FIG. 1B generates a local frequency that enables transmission of the wireless channel CH1. A control signal is received from the control section 140 to cause the control to occur.

Further, the switch 122-2 is also turned to the synthesizer 1212 side and becomes fixed. Next, the calling control signal output from the telephone unit 101 is sent out using the wireless channel CHI. This control signal is controlled by the frequency band shown in FIG.
It is sent using un.

The transmission of this control signal is limited to time throwers 1 to 1 (Sun), and is sent in bursts, and no signals are sent during other times, so it will not adversely affect other communications. However, the control signal If the speed of the signal is relatively slow or the amount of information in the signal is large, one time slot
If the data cannot be accommodated within the frame, it is transmitted one frame later or further using the same time thrower 1 in the next frame.

Specifically, the following method is used to capture sun into the time thrower+. The control signal transmitted from the radio base station 30 includes a synchronization signal and a subsequent control signal, as shown in FIG.
By receiving this, frame synchronization becomes possible. This control signal also includes the current time
Contains control information such as slots and unused time slots (empty time thrower display). Depending on the system, when the time slot SDi (i = 1.2°..., n) is used for other communication, it may contain only a synchronization signal and a call signal, but in such a case However, the unused time slots usually contain a synchronization signal and a control signal, and by receiving this control signal, the mobile radio 1100 determines which time slot should be used to send out the calling signal. can be known.

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 in any of the time slots, in which case the following audio multiplex signals SD1, SD2 . ..., S
It is necessary to search for the presence of Dn 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 time slots 1 to Sun for uplink signals are empty slots, it is decided to use these empty time slots, and the control signal for calling is sent out, and the necessary timing is determined from the response signal from the wireless base station 30. It is possible to extract a burst control signal and send out a burst control signal.

If there is a call from another mobile radio at the same time, the call signal will not be properly transmitted to the radio base station 30 due to a call collision, and the operation will have to be restarted from the beginning. When viewed as a system, this value is kept to a sufficiently small value. If call collisions are to be significantly reduced, the following method may be used.

Even if the mobile radio device 100 finds an empty time slot in which it can make a call, it does not use the entire time slot, but rather uses only the first half of the time slot for some mobile radio devices and only the second half for other mobile radio devices. This is a method that allows you to use In other words, as a calling signal, the portion of the 5 6 time slot used is divided into several types, and this is used to classify a large number of mobile radio devices into groups, and each group is assigned a time slot within that one time slot. This is a method of giving a belt.

Another method is to create many different frequencies for the control signal,
This is a method of dividing a large number of mobile wireless devices into groups and applying this to each group. According to this method, even if control signals of different frequencies 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 when used together, the effects 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 (3202). Search for time thrower i~. The time slot given to mobile radio 1100 may be Sun, but a search is performed just to be sure. It is mobile radio 1
100, it is also used to accommodate simultaneous calls from other mobile radios, and to provide time slots suitable for service types and service classifications.

As a result, if the time slot SD1 is vacant, for example, the time slot SD1 of the radio channel CHI is used for the mobile radio device 100, and the time slot uplink (mobile radio device 100 → radio base station 30 ) SUl.

and instructs to use the corresponding downlink (radio base station 30→mobile radio device 100) SDI (S203
>.

In response, the mobile radio device 100 transitions to a state in which it can receive data in the designated time slot SD1, and at the same time, the mobile radio device 100 shifts to a state in which it can receive data in the designated time slot SD1, and in the time throwers 1 to 1 for the uplink radio channel corresponding to the downlink time thrower l-SD I. A certain 5U1 (second
(See Figure A (b)).

In the control unit 140 of this Togi mobile radio 100,
The transmission/reception intermittent controller 123 is operated, and the switch 122-
1 and 122'-2 are started (3204>).

At the same time, a slot switching completion report is sent to the radio base station 30 using uplink time slot SU1 3205
>, wait for dial tone <8206>.

Time slot SU of the radio carrier of this upstream radio signal
The state of No. 1 is schematically shown in FIG. 2B (C). In addition to the time slot SU1, the radio base station 30 receives 5IJ as an uplink signal from another mobile radio 1100.
3 Sun is included in one frame and sent.

The radio base station 30 that has received the slot switching completion report (
S207>, sends a calling signal to the gateway exchange 20 8208>, which is received by the gateway exchange 20, detects the ID of the mobile radio 100, and selects the required one from among the switch groups included in the gateway exchange If&20. Turn on the switch (
3209>, send dial 1 to -n (3210
, Figure 4B).

This dial tone is transferred by the wireless base station 30 (S211>, and the mobile wireless device 100 confirms that the communication path has been set (3212).

When transitioning to this state, the telephone unit 1 of the mobile radio [100]
You will hear a dial tone from the 01 receiver, so start sending out dial signals. This dial signal is speed-converted by a speed conversion circuit 131 and sent to the transmitter 1.
34 and a wireless transmission circuit 132 including a transmission mixer 133
The dial signal is transmitted using uplink time throwers 1 to SU1 (S213>).The thus transmitted dial signal is received by the radio receiving circuit 35 of the radio base E30.

This radio base station 30 has already responded to the calling signal from the mobile radio 100, gives a time slot to be used, and operates the signal selection circuit group 39 and signal allocation circuit group 52 of the radio base station 30. So, time for the uphill.
time thrower) ~ SU1 is received, and downlink time thrower 1 ~
It is now in a state of transmitting SDI signals. Therefore, the dial signal transmitted from the mobile radio 100 passes through the signal selection circuit 39-1 of the signal selection circuit group 39, and then is input to the signal speed restoration circuit group 38, where the original transmission signal is restored. , the call signal 22 via the signal processing section 31
-1 is transferred to the barrier exchange [20 (3214>), and a call path to the telephone network 10 is set to 0 (3215).On the other hand, an input signal from the barrier exchange 120 (initial control signal, call signal)
is subjected to speed conversion at the signal speed conversion circuit group 51 in the wireless base station 30, and then is given a time slot SD1 by the signal allocation circuit 52-1 of the signal allocation circuit group 52. Then, the mobile radio 141 uses the time slot SDI of the downlink radio channel from the radio transmission circuit 32.
Sent to 00. The mobile radio device 100 is waiting for reception in the time slot SDI of the radio channel CHI, 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 the transmission is restored and input to the handset of the telephone section 101. Thus, a call is started between the mobile radio 100 and a regular telephone within the regular telephone network 10 (3216).

The call is terminated by on-hooking the handset of the telephone unit 101 of the mobile radio device 100 (S217>, by transmitting the end-of-call signal, the on-hook signal from the control unit 140, and the speed conversion circuit 1).
31 from the wireless transmission circuit 132 to the wireless base station 30 (3218>), and the control unit 140 stops the operation of the transmission/reception intermittent controller 123 and switches the switches 1221 and 122-2 to It is fixed to the protruding horn ends of the risers 121-1 and 121-2.

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 is received from 00, the call termination signal is forwarded to the barrier switch 20. 5219>, switch group (not shown)
Turn off the switch () to end 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 between the radio base station 30 and the mobile radio device 100 are controlled by the signal speed conversion circuit group 51. Although it was explained that the signal speed restoration circuit group 38 etc. are not passed through,
This is for convenience of explanation, and like the audio signal, the signal speed conversion circuit i'l' 51, the signal speed restoration circuit group 38, the control signal speed conversion circuit 4B, and the signal C through the signal processing section 31 do not cause any trouble. Communication can be carried out without any problems.

(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 100, the mobile radio 100 is in a waiting state to receive a downlink control signal of the radio channel CH1 according to the procedure defined by the system.

Assume that an incoming call signal to the mobile radio device 100 arrives at the radio base station 30 from the general telephone network 10 via the barrier switch 20. These control signals are transmitted as communication signals 22 to the control section 40 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 selects an empty slot among the downlink time slots of the radio channel CH1 addressed to the mobile radio device 100, for example,
Using Dl, the ID signal of the mobile radio 11100, the incoming call signal display signal, and the time slot usage signal (mobile radio 11
For example, SU corresponding to SDI is used for transmission from 100.
(using l). In the mobile radio device 100 that received this signal 3, the radio receiving circuit 135
is transmitted from the receiving section 137 to the control section 140. The control unit 140 confirms that this signal is an incoming call signal to its own mobile radio 100, so it causes the telephone unit 101 to emit a ring tone, and at the same time, calls the designated time slot SD1. Transmission/reception intermittent controller 1 to standby at SU1
23 and switch 122-1.12.
22 starts turning on and off. In this way, the state has shifted to a state in which calls can be made.

It should be noted that it is theoretically explained in Reference 2 that signal transmission is performed in good condition using this system and does not adversely affect other wireless channels in the system, so it will be omitted here. It will be theoretically explained that the CM signal applied to the present invention has multiple load gain, and then its application will be described.

(3) Regarding the multiple load gain of the CM signal transmitted from the wireless base 7430 4 To correlate the multiple load gain of the CM (time division time compression multiplexing) signal with the multiple load gain of the FDM (frequency division multiplexing) signal , First, each channel CH1 of FDM
, CH2, . . . Cl-1n are expressed in the form of a function. As is well known, FDM signals are frequency-converted audio signals and arranged in a line on the frequency axis as shown in Figure 5. This multiplexed signal is often used in coaxial transmission systems and microwave analog communication systems. , multiple load gain has also been incorporated into practical systems and is showing great effects. Note that the spectrum in Figure 5 has one channel.
Although the case of 2 pieces (CH1 to 12) is shown, in general, 1 piece is used.
In addition to 2 pieces, 60,120,480.960,1200.
Many different types are used, including 2,700 pieces.

In the following description, it is assumed that the input audio signal level to the FDM signal or TCM signal is the same. Now, the fifth
Channels CH1, CH2, CH3, etc. in the diagram
The audio signal flowing to CHn (in the case of wired, the frequency band to be transmitted is 0.3 to 3.4 kHz, but in the case of mobile radio signals, it is 0.3 to 3.0 kHz, so we limited it to this value) (t), f2 (t).

......, f, (t). The frequency components of these signals are 0.3 to 3.0 for channel CH1.
kl-IZ.

C) -12 is 4.3 to 7.0k l-lz, -・
・-・, CHn is 4X (n-1) +0.3~4x
(n-1) kHz, and there is no overlap with each other. However, the amplitude distribution of these n audio signals when viewed from the signal waveform is simply shifted to a higher frequency on the frequency axis, and the signal waveform itself does not change at all. This is important in determining the multiple load gain, and can be expressed as follows. FDM
The known multiload gain of the signal is exactly the same as the signal obtained by arranging r) voices on the frequency axis as shown in FIG. 5 and the signal obtained by simply mixing n voices without frequency conversion.

Prove this using a formula. Channel CH1, CH2,...
..., the Cl-In mixed signal is expressed by the following equation.

F(t) −fl (t) 10f2 (t) 10−+f
n(t)(1) Specifically, f and (t) are expressed as follows.

3kHz (2) (3) However, 1≧2 Further, the mixed signal when frequency conversion is not performed is given by the following equation.

G(j) −ql (t) +C]2 (i) Ten...
Ten. (1) (4) Here, C11(t) -fl(t) kHz (5) (6) However, 1≧2 Next, the power possessed by the signals of equations (1) and (4) is determined.

First, the power of F (t) is (7) On the other hand, the power of G (t) is (8) However, we used the fact that no power is formed between different signals. That is, 7 8 f gigjdt=0 x apj sin (ω, 7+βpj)d↑−〇(9
) However, i≠j Now, from equations (2) and (3), Ding Ding υ (10) (11) However, 1≧2 From equations (10) and (11), F(t) 2=G(t ) 2 (12) is obtained.

That is, it has become clear from the above explanation that the power of a signal is not related to frequency conversion.

Next, consider applying the sampling theorem to q.(1). The highest frequency fh of qB(t) is 3Kl-12
Therefore, the time interval is 1/(2fh), that is, 1/
It is well known that if sampling is performed every 6000 seconds, the original signal can be reproduced later even if only the sample value (voltage value) is transmitted.

As shown in Figure 6A (a), the time interval 9 0 [1/6000+ (1/6000) (i -1)]
Sample every 6000 seconds (13). In the same figure, t, -1/
6000 seconds.

tb - (1/6000) x (1/6000) seconds.

to-(1/6000) x (5999/6000>
seconds.

↑d=1/6000+(1/6000) x (300
0/6000) seconds.

t8-176000 seconds.

It is. Hereinafter, in order to explain specifically, the multiplex number n is set to 6.
000. The length of one frame is 1/6000 seconds.

Now, on the horizontal axis of Figure 6A (a), put 600 small bags (diameter 1/6000 x 1/6000 seconds) as shown in Figure 6B (C).
0 pieces, and one large bag with a diameter of 1/6000 second, are arranged as shown in the figure. Then, compare the above sampled values to matchsticks and consider how these matchsticks fit into the bag.

Since the function Q+ (t) (i=1.2.-, n) has 6000 sticks each in one second, and they are equally spaced in time, the capacity bags (1), (2 ),...,(
One frame is sent to each frame (N), and this operation is repeated once for each frame. That is, Bag (1) has GL (1/6000) Bag (2) has C2 (1/6000+1/6000x 1/6000
) Bag (3) contains g3 < 1/6000 + 1/6
000X 210000) Bag (6000) has CI
(1/6000 + 1/6000000 x5999 /6000) or each will be inserted.

Also, in the large bag (Σ6000), the mixed signal G(t
) is included. In this case, the sampling time is 1/6000+1/
600QX3000/6000, that is, the midpoint of one frame. Then, the value of the next matchstick will be stored in the large bag (Σ6000).

The large bag (Σ6000) has G (1/6000+1/6000x3000/60
00) Below, the value of the match stick from bag (1) to (6000), from (1/6000) 2 g2 (1/6000 + 1/6000xl/6000)
.

C16000 (1/6000+1/6000X 599
The sum of 9/6000) and the value of the matchsticks placed in the large bag (Σeooo>) (1/6000+1/f3000X 3000/
6000) are compared as shown in equations (14) and (15> below).

000 1002 (1/60oo+1/6000xl/600
o) 10g3 (1/6000+1/6000X2/600
0) Ten... +q・ (1/6000+ 1/6000x (i-1
)/6000 ) 106000 (1/6000+1
/6000X 5999 /6000) (14) G (1/6000+1/6000x3000/600
0 ) = g1 (1/6000+1/6000x
3000/6000 )-1-g (1/6000+
1/6000x 3000/6000 > 10Ω. (1
/6000+1/6000X 3000/6000
) (15) As a result of comparing (14> and (15)), if 000 (16) and the average value converges to O every time Δ is sampled at an interval of 1/6000 seconds, then It has been proven that the multiload gain in the FDM signal is similar and has the same value in the TCM signal.This is because 6000 bags placed on the horizontal axis have a capacity of 1 bag. The sum of the bags represents a time slot, and the sum of the bags is one frame, and the match sticks inside the bags correspond to each signal Ω11g2 .
...2go can be considered to be a signal subjected to time division time compression multiplexing (TCM), and the TCM signal is well mixed as shown in the large bag (Σ6.000> in Fig. 6B (c)). This is because it can be regarded as one FDM (number i). Therefore, in this example, even though it is a TCM signal, there is no particular need for time compression, and the degree of compression is 1.

In addition, in Figure 6B (C), the position of the bag on the horizontal axis (axis between #) is as follows for bag (1): 1/6000≦t<1/6000+1/6000
x 1/6000 bag (2) is 1/6000+1/6000x 1/6000≦t<
1/6000 1/6000x 2/6000 Bag (i) is 1/6000+1/6000x (i-1)/6000
≦t < 1/6000 1/6000X i/600
0 bag (6000) is 1/6000+1/6000X 5999/6000≦
t < 1/6000 1/6000x 6000/6
000 is shown. On the other hand, the audio signals J (j), Q2 (j),...J
(t) ,...Ω6000(') The sampling time is 1/600, respectively.
0.1/6000+ 1/6000x 1/6000.
......, 1/6000 11/6000x (i
-1)/6000. ......, 1/6000+
Since it is set to 1/6000x5999/6000, each matchstick will enter one drowning bag while touching the side of the bag. This is done for convenience; if you want to put a matchstick in the center of the bag, for example, change the time t of CJ(t) to t = 1/6000 + 1/6000x (i +0.
5) /6000 should be selected. However, even with this selection, the conclusion of this proof does not change.

Now, compare the corresponding terms on the right sides of equations (14) and (15).

Δ・−〇・ (1/6000+ 1/6000x (i
-1)/6000)q・ (1/6000+1/600
0X 3000/6000) (17) What the above formula means is that when sampling the audio of the first channel (CHi), the time 5 (1/6000+(i-1)/6000") seconds and (1/6000+(i-1)/6000") seconds. 6000+3000/60002) seconds.This difference is like the error value of random noise, and the channel (CHi) i = 1, 2. n
, it may take a positive value, a negative value, or even O occasionally, but in boat fishing there will be variations left and right around O, and the variations will be normally distributed.

The above was related to a certain time 1=18. The next sampling is performed after 1/6000 seconds.

The next one is delayed by another 1/6000 second. Since this sampling is performed, for example, 6000 times per second, the average value of equation (17) for one second is 000 ) lean (ΣΔ, ) −1/6000ΣΔ・→
01=1 (1B) 6 That is, it will approach O. This becomes even clearer if we further increase the time difference, and it can be considered that equation (18) becomes O if we take the average over 10 seconds or 30 seconds.

From the above, it has been clarified that the average power levels of the FDM and DCM signals with the same multiplicity (6000) are the same.Next, the amplitude distribution of the two types of multiplexed signals will be explained.

Here, the signal f(e)(
e=1.2,3. Assume the mean value and variance of ・・・・・・〉 are as follows.

Average value E, [f (tri] = 0 variance E[f
(N) ]-σ2 First, as is well known, the average value and variance of N multiplexed FDM signals are: 7 8 Therefore, they are not arranged on the frequency axis like FDM signals, The above function 0 (i=1.2゜...
. , n) is similarly obtained. The average value is: The variance is Next, the average value and variance of the CM signal used in the present invention are determined. In this case, the function fi(n+k
) is renamed according to the following relationship.

f = (n0k) −f (kN+n++
-1) Now, find the average value.

[-1 E[f(n)]-riim1/I-Σf (n)L-+O
On20For simplicity, let L=rN, then E [f[n)]-1! im(1/rN)r→■ r-IN 1Σ 1/N ffim(1/r) i-1r-+■ -1 9 0 -E [f・ (at)] 10 Next, find the variance .

[→■ n=0 For simplicity, let L=rN, then E [f(n) 2]=l! im(1/rN)r→■ r-+■ -σ2 This makes it clear that the dispersion has the same amplitude distribution as the one channel of the audio signal.

Depending on how the system parameters are taken, when transmitting a CM signal, if the peak value of the signal is large and there is a possibility of increasing the modulation deviation of FM modulation and causing interference to adjacent channels, the σ The circuit for compressing to σ1/2, that is, 1/2 compression (1 in decibel value
The compressor 171 with the function of
It is necessary to insert it as shown in Figure 1F and then add it to the transmitter. On the receiving side, it is necessary to reproduce the original sound after using a circuit that performs an expansion operation, that is, an expander 172 as shown in FIGS. 10 to 1F.

The above is the multiple load gain obtained with FDM,
1 2 This shows that it can also be obtained with M. However, the value of the multiple load gain quoted from the above-mentioned document 3 indicates that the frequency band of the audio signal is 0.3 to 3.
．． 4KH2, whereas in the above example, the audio transmission band is 0, 3 to 3.
It was assumed that the same value could be obtained at 0KH2. This assumption can be accepted with virtually no error.

In addition, in the case of a TCM signal, since the signal is time compressed,
The frequency component it has increases by the degree of compression, but this is because only the frequency component has been changed as mentioned above, and the signal waveform itself has just undergone a similarity transformation to extend it on the frequency axis, so the multiload gain There is no change in the amount, but
Below, we will prove it strictly using mathematical formulas.

The TCM signal is expressed as follows using equations (5) and (6).

However, 4 cho < 1 < cho / n 10 h・ha) - 〇 However, 1/n = 1! Clove<1<Clove ff-1,2
, 3, ...... Below is the time length of one frame. Therefore, the total time-compressed TCM signal is (20) (20) The reason for multiplying by n1/2 on the right side of the equation is that This is due to the fact that only 1/n of the time is transmitted within the time of one frame.This is expressed as a voltage (the power is multiplied by n).Now, find the power of the formula (20) for the time T of one frame. And, similar to equations (7) and (8), 3 4 (21) Therefore, if the time is an integral multiple of the frame, the signal H
The power possessed by (t) and G(t) is H(t) 2=G(
t) 2(22).

Next, the frame length of the audio n-channel multiplexed TCM signal is 1.
The multiple load gain when the value is shorter than /(2fh) will be explained.

In this case, as above, FDM of audio n-channel multiplexing
It can be easily proven that it has a value equivalent to the multiload gain in the signal.

For example, assume that the frame length is 1/8000 seconds. Then, change the sampling frequency to the aforementioned 60001-IZ
to 8000H2, each audio signal Ω1 (t),
g2(t),..., Q, (t) is sampled, and the mixed audio signal G(1) is also sampled as 80001-1.
2, and compare the two. That is, by changing the horizontal axes of FIGS. 6A (a), (b), and 6B (C) from 1/6000 to 1/8000, all of the explanations in section 1 can be applied.

Furthermore, what happens to the multiple load gain when the frame length becomes longer than 1/(2TI,) will be explained. The conclusion is that the multiload gain generally decreases, or
The specific value is determined below. As a concrete number,
The number of multiplexes is 6000, which is the same as the previous example, and the frame length is 1/30.
An example will be explained in which the time reaches 00 seconds. The size of the bags arranged on the time axis is 1 as shown in Figure 68(d).
It becomes larger as the frame length or thickness increases. To be exact, the diameter of the container is 1/6000 x 1/3000 seconds.

Then, if we add up all the diameters of n bags, we get 1/30
00 seconds. Also, the diameter of the large bag (Σ6000) is 1/
It will be 3000 seconds.

Now, as above, the sampling frequency is 17600.
Consider putting the Matsutchi stick sampled at 0 seconds into a container. In this case, if the frame length is set to 1/6000 seconds as described above, the following inconvenience will occur. That is, FIG. 6B (d
) As shown in 1/6000 seconds, the bag is (1) ~
(3000), while Matsushibo has 6000.
Since I have books, I can put two books in each bag.

That is, as shown in FIG. 6B (d), bag (1) has audio signals c+1(t) and g2(t), and bag (2) has the same audio signal Q2.
(t) and 03 (t), bag (3) has Q (t) and g4
(t),..., hereafter, '3000' for bag (3000)
Matchsticks (signal values) indicating (t) and 03001(t) are entered. Note that gl (t) is placed in a bag (6000) which is the previous sampling time. On the other hand, the bags (3001) to (6000) do not contain any Matsushi sticks sampled within the last 7 hours, and only the Matsushi sticks sampled within the next sampling time of 176,000 seconds. Each of them was given two drownings.

On the other hand, the large bag (Σ6000) has two matchsticks in one frame, so the two matchsticks are G (1/6000+1/6000x3000/600)
0) and G (1/6000+1/6000x9
000/6000) will be entered.

However, G (1/6000+1/6000X 900
0/6000 ) is the matchstick (signal) sampled within the next 1/6000 second, which is the same as in the case of the above (small).

What kind of goods does the above refer to?

That means that two matchsticks are placed in bags (1) to (3000), which means that each time thrower 1 to 1 of the King CM signal has audio J (t), ``i+1 (t) 2''.
This means that they should be mixed channel by channel. To do this technically, FDM of 2 tyrenel (CH) is required.
This means that a total of 2 (CH)8 x 3000 = 6000 (CH) TCM signals should be created for 3000 slots. And these and large bag (Σ6
The size of the match stick in the previous one in ooo > will be compared in the same manner as described above.

Although this is also a method, it is not a TCM signal in the original sense. Therefore, in order to include only one audio signal in each time slot, the following must be done. 6000 audio signals are divided into two groups, one group can be placed in bags (1) to (3000), and the other groups can be placed in bags (3001) to (6000).

This operation will be explained using FIG. 6D (f>).

There are bags (1) to (6000) and large bags (Σ600).
0) are prepared. Now, the bags (1) to (6000) written at the top have Matsubo C]1,
G3.

g5. . . , q5999 each shows one water droplet. And for the large bag (Σ6000), G 1 (1/6000+1/6000x 3000
/6000) One matchstick indicating the number is left.

On the other hand, the bags (1) to (6000) written at the bottom have Matsubo Q2. g4. Q6゜...1g6000 was put in each, and G2 was put in the large bag (Σ6000).
(1/6000+1/6000x9000/6000)
There is one matsuthi stick showing.

By doing as shown in this figure, two match sticks will not be mixed in the same bag, and with the same proof as when the length of one frame is 1/6000 seconds, which was already explained, FDM
It can be seen that the multiplexing gain of the signal (in this case, 3000 multiplexing) is the same as that of the CM signal.

The above explanation can be expressed as follows.

(4) n voices (in this case “)−60
00) is divided into two and expressed as follows.

Gl (t) -C1l (t) +03(t)+...
・10g5ggg(t)(4') G2 (j) =g2 (t) +04 (t) +・
...10g6000m (4") Then, the above-mentioned proof can be performed for each of the above equations. However, the sampling timing shall be performed under exactly the same conditions as above.

In the above explanation, it has become clear that there is a need for grouping in order to obtain the multiple load gain, but it will be explained below that the CM signal requires signal compression.

In Figure 6D (f), it is true that there are people in the upper bag group (1) to (6000) and the lower bag group (1) to (6000), but the TCM When viewed as a signal, there remains some dissatisfaction. That is, the upper bag group and the lower bag group are simultaneous in time, so within one time slot of the TCM signal,
Still gl and 02゜g3 and 04・°°゛・q599
9 and g6000h are supposed to coexist and be 70゛.

Signal compression removes this, and the following method may be used. That is, Ql, g3, ..., q
Regarding 5999, there are two bags (1) and (3001),
(2) and (3002), ..., (3000) and (
6000) in the previous bags (1), (2),
..., accommodated in (3000), Q2, Q4.・
..., ' ``For 6000, do the same for the later bag (
3001), (3002),..., (6000)
to be contained within.

1 To do this, for example, with respect to gl, it is sufficient to create a composite signal with a value of 1. In other words, it is sufficient to create the sum of signals obtained at two adjacent sampling times. Technically, the audio signal is stored in a storage circuit and read out in a time-division manner at twice the speed (duty ratio 50%), and this read signal is sampled at a sampling rate of 1/3000 seconds. The signal is what you want. However, in this case, faithful reproduction of the original signal is not possible with the instantaneous value of the CM signal (voltage value) of the zumbling time, and it is necessary to transmit a signal with a fixed time width (time slot l ~ length). There is.

If the above operation is viewed from the viewpoint of multiple load gain, it will be as follows.

If the frame length is longer than the sampling time interval of 1/6000 seconds, even if the number of multiplexes is n or 6000, 600
0CI-1 multiplexed FDM (multiple load gain is 1W
The frame length is 1/3000 seconds and Ico 1.
, equivalently, the multiload gain of the FDM signal is 3000C1-(.

2 Find the multiple load gain when the frame length is roughly 1 second and the multiplex number n = 6000.

An explanatory diagram in this case is shown in FIG. 6C (e). To explain the figure, one frame is one second, and n = 6
000, the diameter is 1/600 on the horizontal time axis.
There are 6,000 0-second bags, which form one frame. In this case J(i),...
``6000 (t),'' consider where the sampled matchsticks should be placed.If the sampling timing is the same as when the frame length is 176000 seconds, then the bags (1), (2), (3 ).

... (6000) will each have one matchstick indicating each audio signal.

On the other hand, in the large bag (Σ6000), there are 6000 matchsticks (with values sampled at each sampling period) indicating G (t).This means that each time slot of the CM signal This means that 6000 channels of audio are mixed and input.The technology that makes this possible is FDM, or the technology that makes this possible is FDM, which is the purpose of this application
Cannot be applied to signals. In the past, in order to have only one audio signal in each time slot, 6
000 audio signals must be divided into 6000 groups, one group at a time (in this case, one channel at a time).

This shows that the multiple load gain in this case is 0 and cannot be obtained at all. Also, TCM in this case
The signal compression degree of the signal is 6000.

As is clear from the above explanation, it has been shown that when the time length of one frame is longer than one sampling period, which is necessary to faithfully reproduce the audio signal, the multiple load gain decreases. - Expressed in the shell, the frame length t. or t e > 1 / (2f h), and when the number of multiplexes is n, the multiple load gain (J5, n' = rlX1/
(2'fhto) (23) This value is equal to the multiple load gain 1q of a frequency division multiplexed signal having a multiplex number determined by the following value.

According to the above-mentioned documents 1a and 2, the practical range of the frame length 4-o and the number of multiplexes n is determined by the frame length t:
0.1 seconds ≧ to ≧ 0.0005 seconds e Multiplex number n: 3000 ≧ n ≧ 2, and as long as it is within the above range, it is clear from the above example that equation (23) always holds true. .

In addition, in order to address one match stick in eight bags as a TCM signal, in other words, to input one original audio signal, the time length of one frame ↑ 8 is longer than 1/2 fh. If the signal has to be compressed, the compression ratio ψ is ψ−t. It was also revealed that it is given by /(1/2fh).

(4) Regarding the multiple load gain of TCM signals received at the radio base station 30 The radio base station 30 receives multiple CM signals transmitted from a large number of mobile radios 100. Consider the multiple load gain with To conclude, as will be described later, the mobile radio device 100
Assuming that exactly the same multiple load gain as in the case of transmitting from 0 to 5 can be obtained, it is understood that transmission may be performed with a deeper modulation factor.

However, if the compressor (group) 71 is used in the radio base station 30 as shown in FIG. 11 or 1,
It is also necessary to insert a module 9171 in front of the wireless transmitter circuit 132 on the mobile radio device 100 side, as shown in FIGS. 1D to 1F.

As a specific example, 1 frame length is set to 1 sampling time interval.
/6000 seconds and the number of multiplexes is 6000. It is assumed that the radio base station 30 is communicating with 6,000 mobile radio devices 100 simultaneously using the same carrier wave and using all 6,000 time slots of one frame.

The positions of the mobile radio devices 100 are arranged at equal intervals on the same circumference when viewed from the radio base station 30, and the receiving antenna of the radio base station 30 is omnidirectional, and the transmitting antenna of the mobile radio device 100 is also omnidirectional. And the magnitude of the transmission power from each mobile radio 100 is all the same, and each mobile radio 1810
It is assumed that the carrier waves used to transmit 0 are phase-synchronized with each other. Furthermore, it is assumed that the radio wave propagation characteristics between the mobile radio device 100 and the radio base station 30 are the same regardless of which mobile radio device 100 and the radio base station 30 are used. Under the above assumptions, each mobile radio device 100 entering the radio base station 30
The transmitted signals will be received exactly the same. Therefore, the appearance of the received signal within one frame in this case can be considered to be exactly the same as when it is transmitted from the wireless base station 30. Conversely, each mobile radio 81100
Although it is transmitting only a single voice channel in a given time slot,
Assuming that a multiple load gain can be obtained, it is shown that transmission may be performed using a modulation depth that allows for a multiple load gain of 6000.

Although ideal conditions have been set above, consider the actual system operating conditions. In this case, the positions of the mobile radio devices 100 are randomly scattered, and the radio wave propagation state changes in various ways, so the received power of the radio base station 30 varies for each time slot. Furthermore, the carrier waves from each mobile radio device 100 are not necessarily phase-synchronized.

Therefore, if the depth of modulation is large in a time slot where the reception level is high, it is expected that the adjacent time slots will be adversely affected due to the influence of multiplex radio wave propagation. However, this can be alleviated by taking other measures such as increasing the guard time.

In addition, in the case of the small zone method, as same channel interference,
There is no need to worry too much about the possibility that the transmitted waves of one mobile radio 11100 may cause interference to other radio base stations 30 that are located in different locations; on the contrary, it may be possible to use this to gradually reduce the number of repeated zones. . This is because multiple load gain is used as FM (PM) modulation, and as a result of deep modulation, wideband gain can be obtained and resistance to co-channel interference is increased.

Taking all the above into account, the system design assumes that substantially the same multiload gain can be obtained when the mobile radio device 100 transmits and when the radio base station 30 receives, as when transmitting from the radio base station 30. It became clear that it could be done.

(5> Specific utilization method of multiple load gain The multiple load gain is calculated in the case where one frame length is 1 m5ec and the number of TCM (time division time compression multiplexing) is 500, and an example of its utilization will be explained.

First, S CP C (Singte Channel
Per Carrier.

The signal of one telephone channel is modulated on one carrier wave. Find the signal S to noise N ratio of analog FM, and combine this with TC.
Compare with M. The level (voltage value) of the input signal to the receiver is C, the FM modulation index is mf, the noise level (voltage value) per unit frequency is F, and the bandwidth of the low frequency amplifier in the output stage of the discriminator is Fa. The highest modulation frequency f of the wave is F8
, the signal-to-noise ratio is given by the following formula.

S/N-31/2mfC (2Fa>-172(24) In addition, this formula was quoted from the following literature.

Edited by Sugawara "FM Radio Engineering" Published by Nikkan Kogyo Shimbun Co., Ltd., 1960, p. 401 (13, 25).
The S/N in this case is given by the following formula.

(S/N) DCM = 31/2"fQcQ (2FaO) -""(25> However, "ao-QFa mfQ=Qmf (25'>n Q
= Q n In other words, in the TCM signal, the frequency of the original signal is multiplied by Q, so the bandwidth t of the low frequency amplifier increases by IQ times, and the modulation depth (modulation index) also becomes Q times, so Since the noise level is also Q times the bandwidth, (25'
) is appropriate.

Next, the received signal level C8 of the TCM so that the S/N on the left sides of equations (23) and (24) take the same value is determined by the following equation.

0 1/2 3mfQCQ(2FaQ)-172 (26) From equation (26), we obtain c, =Q''C(27>.In other words, the reception level is 017 in voltage.
2 times, which means that Q times the power level is required. Therefore, the transmission power needs to be increased by Q times from 5CPC.

Next, find the multiple load gain of the TCM signal in the above example.

As already explained in section (3), in this case FDM
The equivalent multiplex number is n'-500xl/6000 (sec) ÷ (1/
1000 (sec)-500X1/6 =83 0
H Therefore, it can be seen from FIG. 11 that the multiple load gain is an intermediate value between 28.6 dB for 60 channel multiplexing and 32.6 dB for 120 channel multiplexing.

When the graph shown in FIG. 10 is created and estimated based on FIG. 11, a multiple load gain of 30 dB is obtained. Therefore, this multiple load gain is used to deepen the modulation depth (deviation) and reduce the transmission power. 5CPC1 that has not been commercialized
In other words, if the transmission power of the M signal is 10 mW, which is at the cordless telephone level, the required transmission power in this case can be found by multiplying by 500 using equation (27) and then subtracting the multiple load gain, and is 101og ( 1101o 500) -30dB=7d
Bm(28) That is, 5.0 mW is obtained. This means that using TCM requires less power.

Next, the physical meaning of multiple load gain in TCM signals will be explained, and points to be noted when using this as a system will be described.

The TCM signal has a long frame period of 1 second (the number of multiplexes is 6).
000), no multiload gain can be obtained; however, in this case, the FM of the TCM signal
The modulation index has a constant value defined by the system. For example, if the modulation index of the original signal (0, 3 to 3.0 KHz > is 1.75 KH2 (1 KH2 tone signal with standard modulation deviation), this is multiplexed with 500 CMs.
In this case, the signal band is 150 to 1500 KH2, and the standard modulation deviation is 875 KHz (when a tone signal of +-12 to 500 is modulated as standard). However, if the frame length is set to 1m5eC, a multiple load gain of 30 dB can be obtained as described above, and this multiple load q is used to increase the depth of modulation, but what is the actual state of the modulated wave? Explain what is happening.

First, consider an all-channel implementation, ie, a telephone signal is flowing in all time slots. In this case, the effect that a multiple load gain of 30 dB has on the increase in modulation deviation is that, considering from Figure 12, the multiple load gain is the value obtained by subtracting approximately +8 dB as the relative power of the sine waves with equal peak values. It can be seen that it is equal to the modulation shift of the signal when only one time slot is used in a TCM signal having an arbitrary frame length.

Next, consider the case where the load is gradually reduced from all time slot implementation to light3. That is, what happens to the modulation shift of the signal when some percentage of the time slots are used for actual audio signal transmission and the rest are not used as idle time throwers?

In this case, since the number of installed channels is reduced, the multiple load gain is also naturally reduced. For example, 1/2 25
0 implementation, the multiple load gain is n'-250xl/6000÷(1/1000)-25 from equation (23).
0X 1/6 = 42 (CI-1>Therefore, the first
It can be seen from Figure 0 that the multiple load gain is 24.5 dB. However, since the load is 172, the power level of the modulated signal is lowered by 3 dB. Therefore, the equalizing multiple load gain in this case is 27.5 dB, which is equal to
Although the effective modulation depth of M-FM is slightly larger, this is considered to have no effect on system operation.

Find the effective modulation shift when the number of implementations is further reduced and only one time slot is used. The multiple load gain for one channel is OdB, but the signal load is 11500 compared to the full implementation, that is, 2
It has decreased by 7dB. Therefore, the apparent multiple load gain is 27 dB, and even if the modulator is operated with this gain set to 30 dB, it may be assumed that there is no effect on system operation. In addition, in the input stage of the modulation circuit of an actual radio, I D
C (In5 tantaneous deviation
n Control (instantaneous modulation deviation amount suppression) circuit is provided, and has a function of limiting the modulation depth to a certain value or less. Therefore, the modulator output is TC
Regardless of the implementation state of M's telephone signals, the effective modulation deviation is kept below a certain value.

As explained above, by using the multiple load gain of the CM signal to increase the modulation deviation of the FM signal,
It has become clear that the transmission output can be significantly reduced. Technically, this means that it has a very large effect on power saving.

That is, it is obvious that the power saving effect is large since a radio device with 5 cpc and continuous transmission of 10 mW is operated at a time rate of 11500, that is, 0.2%, and the output is only 172 mW of 10 mW.

Next, a system comparison is shown in FIG. 7 when the frequency bands of cordless telephones currently used in Japan are used in the CM system, and the present invention will be explained in detail.

In FIG. 7, various characteristics of various types of CM systems, dress telephones, and FDM systems are listed for comparison. Here, the abbreviations of each c1 specification will be explained.

fC...Carrier frequency NC...Number of required wireless channels n...Number of possible calls (calls) N...Maximum number of calls as a system maX fw...Frequency band of modulated signal Vllll...Modulator Maximum voltage for input stage (1/6
000 seconds average) q'...'sW by multiple load (estimated from Figure 10) V
qm... Maximum voltage (average for 1/6000 seconds) Md...
・Modulation depth (standard modulation) 2 units...Transmission power A3...Service area (distance from wireless base station)
to...1 frame length NTS...number of time slots in one frame n'.
...FDM conversion multiplex number (calculated from formula (23)) In Fig. 7, the numbers of systems 1A, 1B, 2.
In 3, the maximum number of calls N as a system is calculated using the frequency band 12.5 kHz x 89 CH = 112.5 kHz given to the one-way station max of the cordless telephone with one CM-FM signal of one carrier wave.From Reference 1,
It can be seen that up to 148 channels (CH) can be used with 148 multiplexing, that is, a ]-dress telephone line. The frequency band fw of the modulation signal of the FDM system in the figure was calculated as 444 kHz for system comparison. Mata Ding CM
The multiple load gain q' of system 1B is OdB when calculated from equation (23), but for comparison with system 2, it is calculated as the number in parentheses.

7 Number of multiplexes in TCM system 2 in Fig. 7 (time throwers 1 to number N□8 in one frame > 148, frame length t
. Find the multiple load gain of the CM signal of -1m5ec.

As shown in equation (23), in this case, the FDM equivalent number of multiplexes is 211.6CI-(Therefore, from FIG.
It is known that this value is an intermediate value of 32.6 dB for H multiplexing.

Estimating from Fig. 10, we obtain 21 dB. Therefore, this is used to deepen the modulation depth (8 shifts) Md and reduce the transmission power P1. Not using TCM 3 (:,
Single Channel Per C
In other words, if the transmission power of a 1-channel analog FM signal is lQmW at the cordless telephone level, the required transmission power in this case is 1 from equation (27).
It can be found by multiplying by 48 and subtracting the multiple load gain.

That is, 10 jog (10mWX 148)-21dB=
Obtains 11.7dBm. Time rate is 1/1 when using TCM
The transmission time will be 48 times, and the transmission power itself will be approximately the same, 8 times. However, 17
It is necessary to install a compressor 71.171 of about 2 compression to suppress the peak output.

Since the DCM system shown in FIG. 7 cannot obtain a large multiple load gain q' like the FDM system, it is inferior to the FDM system in terms of gradual reduction of the transmission power P1.・Since it is intermittent transmission using slots, the average power is FD
It will be on the same level as the M system. In addition, considering that the hardware configuration of the mobile radio device 100 of the Ding CM system is much simpler and cheaper than that of the mobile radio device of the FDM system, the Ding CM system is It has become clear that this system has higher frequency utilization efficiency and is more economical than both cordless telephones and FDM systems.

In addition, in the CM system, one frame length is t. The shorter is, the larger the multiple load gain can be, but it cannot be made too short. For audio signals, the length of one frame is t. This is because if the number of samples is short, the number of samples cannot be increased, making it difficult to faithfully reproduce the original sound. Practically, one frame length to is about 1 to 5 m5ec.

(6) Physical meaning and considerations of multiple load sequence 1q in CM signal The TCM system of FIG. 7 will be compared again. system 1
In A, each time slot S as shown in FIG. 8(a)
The signal of 1 second of audio is compressed to 1/148 second,
After being FMed, it is sent out into space, whereas in Fig. 8 (b
) system 2, the signal of 1/1000 seconds of sound is further multiplied by 1/148, subjected to FM, and then sent out into space. Hereinafter, in system 1A, the modulation depth Md must be maintained at 1.75 rad rm, s, similar to a cordless phone, whereas in system 2, this must be maintained at 21 dB.
Let's consider the physical reasons why it is okay to deepen the depth.

First, in system 1A, a comparison is made between system 1B and system 2, in which the transmission power PT is lowered by 21 dB than the value shown in FIG. 7, and the modulation shift keying depth Md is increased by 11.2 times (21 dB). think of. However, ID
C (1st modulation deviation amount suppression) circuit and compressor 171.
Expander 172 supports system 1B and system 2.
Assume that it is not used in both systems.

If the influence of radio wave propagation characteristics such as multiple wave propagation on communication is not taken into account, and if other design specifications are taken into consideration, both systems will Both should be able to be received with the same reception quality.

Next, we examine the influence on adjacent wireless channels. system 1
In B, there are many cases where an audio signal, for example, "Apa" is transmitted at a high level for 1 second, and therefore TCM
Even after 1/148 seconds, the modulation deviation is, for example, 1.
Sending a modulated wave into space at 11.2 times the 75 rad rms will reduce the transmission power to 11.7 m.
It will be demonstrated below that even if it is reduced significantly, it will cause significant interference to adjacent channels or other communications.

1 Quantitatively find out how much larger it is compared to System 2. For this purpose, it is sufficient to compare the signal powers of systems 1B and 2 that exist within a certain period of time. However, if the time for this is set too long, the comparison becomes meaningless, so here it is set to 17148 seconds. Then, in system 1B, the high level signal (voltage value VlllX 1 second) lasts for 1/14 B seconds, so the total power @E1 is E 1-1 / 2 Vm X 1 / 148 (2
9) When comparing VIIl with System 2, it should be noted that it corresponds to the case where all time slots 81 to 8148 in one frame of System 2 are all peak voltage values (however, this will be explained later). )

On the other hand, in system 2, a high level signal (voltage value VII
IX1/100 seconds), how many of the 148 multiplexed signals are there, and how many medium or low level signals are there, but they are equal in electric potential. In other words, if V is the 2 voltage of each time slot, the total power ``2'' is E2 = 1/2ΣVi Xi/148 (30) The total power IE2 can be estimated to be more approximate than the value in Figure 11. In this case, it should be considered as around 15 dB instead of +9 dB, so finding the ratio r between equation (29) and equation (30), r=201og148-0.15=28 (dB)(3
1) From the above, the power of the signal input to the modulator of system 1B within a certain period of 1/148 seconds is
It was found that the modulated wave is 28 dB higher than that of , and therefore the modulated wave is subjected to a large modulation shift (modulation depth), which may cause large interference to adjacent channels. However, the above level difference of 28 dB should actually be exactly equal to the multiple load gain of 21 dB. This is because if the comparison time and peak power amount are selected accurately, there will be a difference in multiload gain between 1 audio channel and 148 audio channels (24.6 channels in FDM conversion).

The above results can be further explained as follows. System 1B stores high-level audio signals for as long as 1 second, compresses the time, and sends them out as FM signals within 1/14B seconds, whereas System 2 stores high-level audio signals for only 171,000 seconds. It is stored in memory and compressed to 1/14B. The same process is then performed for the other 137 time slots within one frame, and various signals such as high-level audio, medium-level audio, or mostly silent audio are generated within 171,000 seconds. They are arranged in chronological order and sent out into space as FM signals.

As a result, the input signal level of the modulator within one frame of system 2, and thus the amount of modulation deviation (modulation depth Md), is lower by the multiple load gain (21 dB) compared to system 1B. Therefore, interference to adjacent channels is also reduced by the amount of modulation shift. Of course, it is clear that the modulation deviation amount of system 1B does not cause interference if the audio signal within one time slot is silent, but in system 2, because the time of one frame is shortened, While the average power within one frame is low, in the system 1B, this average power is not constant and fluctuates greatly.

This is the problem.

(7) Countermeasures against peak modulation deviation of the CM-FM signal As explained above, it is clear that if the multiple load gain of the TCM system is used to increase the amount of modulation deviation, the transmission power can be significantly reduced. Now, we will explain countermeasures against peak deviation (peak modulation deviation).

Although it is small in terms of time probability, peak deviation (peak modulation deviation) also occurs in the CM-FM signal (system 2 described above), and this may cause adjacent channel interference. I can't deny it.

First, as used in mobile communications in general, the input stage of the modulation circuit of a radio is equipped with an IDC (In5 tantaneo).
Us Deviation Contro! It is sufficient to provide a function of limiting the depth of modulation to a certain value or less by providing a circuit (instantaneous modulation deviation amount suppression). If this is used, the maximum modulation deviation of the modulator output will be kept below a certain level, regardless of the TCM telephone signal state.

In addition, as another countermeasure, microwave analog
-1800CI-1 etc.) experience with the system would be helpful. In the microwave analog system, a bandpass filter is inserted into the transmitter output (antenna feed line input) to remove high-order sidebands of the FM signal and prevent interference with adjacent channels. A method exactly similar to this may be adopted for the CMFM.

(8)] Regarding the use of an expander, a compander is a compressor (compressor) and an expander (
This is a general term for combinations of expanders, and those used in analog voice communications operate in response to the envelope level of the voice, and are also called syllabic companders, which are currently widely used.

Generally, in mobile communications, the reception level fluctuates significantly by 20 to 30 dB due to fading, so the reception S/N (signal-to-noise ratio) deteriorates significantly compared to when there is no fading, and when the reception level is considerably high. However, various noises enter during the call, resulting in unpleasant interference. Noises include thermal noise, click noise, and random F.
There is M noise, but the click noise is especially audible when there is no call, and even if the line is designed to ensure sufficient clarity of single tones, it will greatly deteriorate the subjective evaluation.

] N'Panda has the effect of increasing the voice level in the wireless section during a call and improving the S/N ratio, and greatly suppresses the noise generated in the wireless system when there is no call, making it an extremely useful technology for improving call quality in mobile communications. It is a powerful tool.

In the present invention, a compander similar to the above is used to compress the peak value of the CM signal. The specific system configuration and operation will be explained below.

1D and 11 respectively show a mobile radio device 10.
This is an example in which a compander is applied to 0 and a radio base station 30. In FIG. 11, a compressor 71 is inserted between the signal allocation circuit group 52 and the wireless transmission circuit 32, and compresses the amplitude of the time compression multiplexed signal. An example of this standby compression characteristic is shown in FIG. 9A.

The compressor characteristics in FIG. 9A are n1 for input signal n.
Since it gives an output of /2, it is called 1/2 compression. That is, if the input h level changes by 1QdB, the output level will change by 5dB. Therefore, the distribution of amplitude characteristics of the audio signal becomes 1/2 in decibels. Therefore, when the signal enters the wireless transmission circuit 32, the amplitude distribution of the signal applied to the wireless transmission circuit 32 is 1/2 in decibels compared to when the signal is not compressed by the compressor 71.

On the other hand, in the case of an FDM signal, since the amplitude distribution is proportional to n1/2 of the multiplexing number as explained above, the CM signal passing through the above-mentioned amplifier 71 is considerably larger than that of the FDM signal. This results in a suppressed amplitude (i5).

Now, suppose that an amplitude-compressed signal is transmitted from the radio base station 30B from the antenna and received by the mobile radio device 1008. As shown in FIG. 1D, the configuration of the mobile radio device 100B is such that the time-compressed audio signal of the received signal is input to an expander 172 inserted on the output side of the receiving section 137. Ru. This input signal is the 9th A
It will undergo transformation according to the expander characteristics shown in the figure.

That is, when the input level changes by 5 dB, the output level changes by '1Q dB. As a result, as shown in the center of FIG. 9A, the overall characteristic is that for every 1 dB voice input change on the transmitting side, the receiving side telephone input change is also 1 dB, and the original signal is faithfully reproduced.

The above explanation is transmitted by the radio base station 30B and transmitted by the mobile radio device 1.
Although we have explained the case where 00B is received, mobile radio 100
The same applies to the case where the wireless base station 30B transmits and receives the wireless base station 30B. Thus up.

In the case of downlink calls, the user will hardly notice the presence of the compander, and it is expected that the call quality will be improved.

In addition to those with 1/2 compression and (expansion) characteristics, there are also Hunpandas that have arbitrary ratios (a/b) of 9 compression (expansion) characteristics. Even in the 1T diagram, 1/
In some cases, it may be appropriate to use a panda with characteristics other than 2, and the decision must be made while considering the system conditions.

Plus companders (compressors and expanders)
By using , it is possible to equivalently convert the multiple load gain of the lower CM multiplied signal into the FDM multiplex number (25) to increase the gain beyond the value obtained from equation 25. However, in this case, Although it is necessary to pay some compensation such as generation of distortion noise and instability of system operation, in practice, this should be minimized to increase the profit 1q.As an example, take the system 1B in FIG. 7.

As already explained, in system 1B, the multiple load gain q−
is OdB as long as it is determined from equation (25), and it has been explained that increasing the modulation shift of the modulator causes interference to adjacent channels. However, considering that a compressor with a high compression rate is inserted into the modulator input and the 00 peak value is removed by an instantaneous modulation deviation suppression circuit, the modulated wave is modulated by the CM system 1A due to the function of these circuits. Even if the shift (modulation depth Md) is increased by, for example, 20 dB, modulated waves without interference can be obtained in adjacent channels. This will be explained further.

The characteristics of compressors CA and CB used in the CM systems 1A and 1B of FIG. 7, respectively, are shown in FIG. 9B. In FIG. 9B, the horizontal axis shows the input level of the two types of compressors CA or CB, and the vertical axis shows the output levels of C and CB. Point A and point B on the horizontal axis are respectively TC
It shows the average human power level for one frame time of M systems 1A and 1B. It should be noted here that although points A and B are average power over one frame time, they relate to one frame that includes a high level of signal power. The high level signal power mentioned here is (30)
This refers to the power of the high-level signal mentioned in the process of deriving the formula.

The compression ratio of the compressor in this example is CA is 1/2 (output change is 1 dB for a 2 dB change in input>), C8 is 1/1
0 (output change of 1 dB for a 10 dB change in input).

Now, in the CM system 1A, the input level is tJ, point A, and assuming that a 1/2 copper plane with a compression ratio of 1/2 is used, the peak value will be 10 dB higher than the point A. The output level of the compressor/resser OA will be suppressed to 5 dB, but the output of the compressor CA is equipped with an instantaneous modulation deviation suppression circuit, so the output level will be completely suppressed by 3 dB and the modulation will be suppressed. A level higher than 3 dB will not be applied to the device.

On the other hand, since the Ding CM System 1B has a long frame time,
Normally, it should be operated at point A because multiple load gain cannot be obtained like in the CM system 2, but since we want to reduce the transmission power of the transmitter (approximately 20 dB), the human power level of compressor CB is set at point A. The level is raised to 8 points, which is 20 dB higher, and this is set as the operating reference level. Then, for an input with the average power of one frame containing a high signal level, the output level will be 2 dB higher, and the system 1
The peak value of the signal B has an operating reference level of 29d.
Since this is a raise at point B, the output level is roughly 10 dB higher than point B, but the increase is only 1 dB due to the amplifier C8, and the output level becomes 3 dB. Once upon a time, system 1A
This means that the output level is approximately equal to the output level of , and no interference will be caused.

The above explanation of the operation was based on the average power of one frame with a high signal level for both system 1A and system 1B, so considering the average power of the CM signal over a long period of time, for example 10 seconds or 30 seconds, the compressor operation The reference level is considerably (approximately 20 dB to the left) than points A and B. However, even for these low input levels, the output of compressor CB is at a high level compared to OA, so
A high level signal is always applied to the modulator.

Therefore, a modulated wave with a large modulation shift can be obtained, making it possible to gradually reduce the transmission power.

In order to reduce the influence of distortion noise on communication as much as possible while obtaining the above advantages, it is necessary to use a compressor with good characteristics and a high compression ratio.

The compander described above has exactly the same principle of operation as the currently commercially available audio funpanda (j), but the required characteristics are different from those for audio (0.3 to 3kl-12) and require advanced characteristics. will be required.

This is because, as is clear from the above explanation, the frequency range of the input signal to the compressor 71, 171 is extremely wide because the audio is time compressed and multiplexed. For example, in the case of 148 multiplexing in the previous example, 148 in the frequency range L1.0.3k l-1z -3kHz
44.4kl-1z-444kl-1z, and as explained above, the signal level fluctuation is not only the deviation σ of the amplitude of one audio channel around the average power value, but also the increase in the level fluctuation of the multiplexed signal. (22 dB in this case) must be assumed. Further, the expander 72.172 used in the receiver must also have performance that satisfies the above operating conditions. In the past, the companders used in the CM-FM system required more advanced technology than the companders for cordless telephones and car telephones that are currently widely used.

The above is a so-called ideal compander required for CIVI-FM, but below, an example will be described in which a practical or economical compander is applied.

For this purpose, consider the application of currently commercially available companders to the present invention. FIGS. 1E and 1J show the configurations of mobile radio 14100C and radio base station 30C in this case. In the configuration of FIG. 1J, a compressor group (signal compression circuit group) 71 is inserted between the signal processing section 31 and the signal speed conversion circuit group 51, and the audio signal is compressed here. For example, in the compressor 71-1, the audio signal is
It undergoes level conversion as shown in the compressor characteristics in Figure A. Once, n audio signals were sent to the compressor group 71.
through the signal speed conversion circuit group 51. Signal assignment circuit 8 yen 5
When the signal enters the wireless transmission circuit 32 via the compressor group 1, the amplitude distribution is 1/2 in decibels compared to the signal applied to the wireless transmission circuit 32 without passing through the compressor group 1.

Now, assume that the above signal is transmitted from the radio base station 30C via the antenna and received by the mobile radio device 100C. The configuration of the mobile radio device 100C is as shown in FIG. 1F, in which the received signal passes through a speed restoration circuit 138 and then is inputted to an expander 172. Here, the received signal is the ninth
It will undergo conversion according to the expander characteristics shown in Figure A. As a result, the original signal is faithfully reproduced as described above.

The above explanation [, 1. Although the case where the radio base station 30C transmits and the mobile radio 100C receives is explained, the same applies to the case where the mobile radio 100C transmits and the radio base station 300 receives. Thus up.

In the case of downlink calls, the user will not feel the presence of the panda at all, and it is expected that the call quality will be improved.

(9) 1 according to the present invention regarding the card time between the time slots 1 and 1 used in T-CM and -FM signals.
Guard tie 44 between the CM signal time points 1 and 1.
Explain the benefits and disadvantages of an example of setting up a

In the above-described CM signal, it is not necessarily necessary to provide a guard time between pulse trains as in a digital signal. However, in order to eliminate the timing shift of synchronization signals and the influence of delayed waves caused by multiple waves on radio wave propagation, guard times may be set between time slots. The numerical value varies depending on the system to be applied, but for example, 0.1 to 0.5 μsec for an indoor mobile phone system and 5 μsec for a car phone.
~10 μsec is appropriate.

In a system with a guard time, if the frame length is constant, the time width of the slot time decreases by the size of the guard time, so the compression ratio of the original signal must be increased. The highest frequency of the signal becomes higher. In the cordless phone example above, the time slot is i m sec ÷ 500 = 2 μsec, and 1
If we take a guard time of 0%, that is, 0.2 μsec, the time slot will be 1.8 μsec. Also,
The highest frequency is 3kl-12X without Gato time.
Taking 10% guard time from 500 = 1.5M+-12, 1.5MH2XIO,/9 = 1.67
It becomes MH2. Therefore, the required bandwidth becomes correspondingly wider, and the frequency effective utilization rate decreases by 11%.

Next, we apply multiload gain to the amplifier design. In this case, the level of the multiplexed voice converted into TCM may be considered to be lower than the level conventionally considered by the multiplex load gain valve. Therefore, even if the amplification factor can be increased by that much, or the output level can be increased to a higher multiple load gain or higher output than before, the distortion factor, etc. will remain at the value conventionally assumed.

Multiload gain is applied not only to active circuits as described above, but also to
It is also applicable to passive circuits as described below. That is, when applied to a mixer circuit, even if the rated output is increased by the level of the multi-load gain valve, it is possible to operate in the conventionally assumed operating state. When applied to a wireless transmitter, this has the following benefits. For example, the first
Inserting a power amplifier into the output of the transmission mixer 133 in Figure B is as follows:
Often used to increase the range of radio waves. In this case, by introducing a multiple load gain, it is possible to increase the transmission output level higher than the conventionally assumed level by an amount indicated by the multiple load gain. Alternatively, if the same transmission level as the conventional one is sufficient, the rated output of the amplifier can be made with a lower level output than the conventional one by the amount of the multiple load gain.

The above concept of rated power can be applied not only to transmission mixers but also to all resistors, capacitors, inductances, etc.

(10) Use of CM signals outside the exclusive frequency band As explained above, when a communication signal is time-compressed, the exclusive frequency band moves to a higher frequency band. For example, the exclusive frequency band of a signal time compression multiplexed to put 148 channels of audio signals on one carrier wave is 44.4k.
H2 to 444kHz, and an unused frequency band occurs from O to 44.4kHz. Regarding the use of this,
This will be explained using FIG. 2C and FIG. 3D.

FIG. 2C is an embodiment showing a frame structure of a system to which the present invention is applied. The difference from the example of FIG. 2A already described is that the synchronization signals inserted in each time slot are combined into an independent synchronization signal. The point is that time slots SCD and SCU have been installed.

By doing this, communication time thrower 1~(SD
1 to SDn, and SU1 to 5un), only communication signals are implemented except for control signals that are required at the start or end of communication, at zone switching during zone transition, and the like.

Now, the exclusive frequency band of the frame configuration in Fig. 2C is the 3D
as shown in the figure. That is, TCM call signals,
Control signals (SD1 to 5Dn) and synchronization signals (SCD) exist at frequencies 44.4 to 444 kl-12;
It does not exist below kl-1z.

Therefore, we are considering implementing other signals in this band to make effective use of the frequency.

Channels CH1 to CH11 in FIG. 3D show one example, in which 11 channels of telephone signals are implemented as FDM signals. Next, the hardware configuration of the system will be explained using FIG. 1F and the first diagram.

FIG. 1F shows an example of the configuration of the mobile radio device 100D, and it will be explained below that in the case of the same figure, a telephone signal carried on the FDM signal can also be transmitted and received on the TCMCM signal. First, an incoming call signal transmitted from the wireless base station 30D shown in the figure is received by the receiving section 137. The control signal for the incoming call signal instructs the transmission method, and either operates the expander 172 and speed restoration circuit 138, which are circuits for receiving CM (time division time compression multiplexing) signals, or The FDM communication path converter 174 is operated after a rest period, and the control unit 140 operates the circuit according to the instructions.

Hereinafter, when transmitting and receiving FDM (frequency division multiplexed) signals, the FDM channel converter 174 is operated and the switches 118-1 and 1111 8-2 are turned on to the FDM channel converters 174 and 173 side. . Next, from the wireless base station 30D, [Which channel of the DM channel converters 173, 174 (C in FIG. 3D) -
11 to 11), the control unit 140 switches the FDM channel converter 173.1 to enable transmission and reception on the instructed channel (channel CH).
74 to operate it.

On the other hand, the wireless base 830D decides to operate the FDM channel converters 73 and 74 for the mobile wireless device 100D among the circuits in its own device, and
The state is changed to using the same communication path (channel Cl-1) given to 0D.

As a result of the above, the wireless base station 30D and the mobile wireless device 100
D is now in a state where it is possible to communicate using FDM signals (uncompressed signal communication), and the already explained TCMC
Communication is started in the same manner as when the M signal is applied.

Depending on the mobile radio device 100, it is possible to simplify the configuration of the performance device 12 by using a configuration that can only transmit and receive lower CM signals or only FDM signals.

Also, the multiple load gain of the composite signal having the signal components shown in FIG. 3D will be explained. As already explained, the multiple load gain of the CM signal is 21 dB when the frame time is 0.001 seconds, and 11 dB.
The channel FDM signal also has a multiple load gain of about 14 dB, as shown in FIG. therefore,
The amount of modulation deviation applied to the modulator included in the radio transmitting circuit 32, 132 shown in FIG.
~43 to 1”z is 14dB, 44.4 to 444kHz
It can be seen that even if the depth is increased by 21 dB, there is no interference in the adjacent channels. However, the influence on the modulation shift of the synchronization signal SCD shown in FIG. 3D was ignored. Even in a practical system, the energy of the control signal relative to the total signal energy is extremely small, so it can be ignored.

The frequency characteristics of the allowable increase in modulation deviation of the above modulator are:
Shown in Figures 2D (a> and (b)).

(a> is a flat characteristic of 14 dB for FDM signal, T CM
(This shows the case where U is given a flat characteristic of 21 dB. (b
) shows the case where emphasis is given to the high frequency band. The effects of enhancement are well known, and FM
Since waves are susceptible to so-called triangular noise, a large modulation shift is applied to signals in high frequency bands to deal with this problem. When demodulating at the receiver, it is natural to apply de-emphasis.

Next, detailed operations of the radio transmitter circuit 132 and the radio receiver circuit 135, which play an important role in the configuration of the mobile radio device 100D that uses the above TCM and FDM composite signals, will be explained with reference to FIG. 1G and FIG. 1H. .

In FIG. 1G, digital/analog signal mixer 2
17 is a control signal from the control section 140.

The signal after being compressed by the compressor 171 or F
One or two of the output signals from the DM channel converter 173 are applied simultaneously, mixed here, and then input to the modulator 216.

A predetermined modulation shift is given by the modulator 216, the signal becomes an FM signal, is added to the transmission mixer 133, and is transmitted from the antenna section as a predetermined radio frequency.

On the other hand, the signal sent from the wireless base station 30D is received by the wireless receiving circuit 135 of the mobile wireless device 100D.
In the reception mixer 136 shown in FIG. 1H showing the detailed configuration, the reception signal from the antenna section is converted into a predetermined intermediate frequency, and after being amplified to an appropriate level by the amplifier 211, it is input to the frequency discriminator 212. . This output is separated by a digital/analog signal separator 213, the digital signal is sent to the clock regenerator 141 and the control unit 140, and the CM signal and FDM signal are sent to the expander 172 via the bandpass filter 214. and is sent to the FDM channel converter 174. Here, amplifier 211 is unnecessary if the signal from receive mixer 136 is sufficiently large.

The above is an example of the operation of the mobile radio device 100D, but the radio base station 30D also has 15 functions similar to those described above, or each radio receiving circuit 35. Wireless transmission circuit 32
is equipped with. Note that the control unit 40 of the radio base station 30 in this case exchanges control signals with the signal processing unit 31, unlike in FIG. 1C. This is because the signal processing section 31 itself cannot determine which of the communication signals should be processed as a CM signal or an FDM signal. The control unit 40 checks the capabilities of the communicating mobile radio device 100D, that is, whether it is capable of transmitting and receiving only CM signals, and the FD
The use of the TCM or DM double signal is determined by considering whether the M signal is also 0-hi between transmission and reception, and the communication traffic condition at that time.

In the above explanation, the FDM signal is placed in the lower frequency band of the exclusive band of the CM signal, but in reality, the FDM signal
It is not limited to signals, ie, any signals such as a data signal, an image (analog) signal, etc. can be implemented. Of course,
A TCM signal in which 11 channels of audio signals are multiplexed may be used. However, depending on the signal, there are some signals for which multiple load gain cannot be obtained, and in that case, the modulation shift amount must be used without increasing.

[Effects of the invention] As is clear from the above explanation, the multiple load gain of time-division time compression multiplexing (DM) signals, which had not been clearly shown in the past, has been quantitatively clarified using system parameters. As a result, for example, the depth of angular modulation (deviation amount)
Even if the transmission is deepened by the amount of multiload gain, the influence on other wireless channels can be suppressed within the conventional design value, and the transmission output level per wireless channel can be reduced to a level lower than that of the conventional system. It became possible to further reduce the amount.

Also, if we increase the modulation deviation by the amount of multiload gain,
When the peak value of a signal is high and there is a possibility of causing interference to wireless channels using adjacent channels or nearby frequency bands, this can be prevented by using a compander, as well as by the use of an amplifier. Rational and economical designs are now possible in terms of design and how to determine the ratings of passive elements. For example, communication using frequency division multiplexed (FDM) signals can also be used in combination. The effect is far greater than that of communication systems, especially wireless systems.

[Brief explanation of drawings]

Figure 1A is a conceptual block diagram showing the concept of the system of the present invention, Figure 1B is a circuit diagram of a mobile radio used in the system of the present invention, and Figure 1C is a wireless base used in the system of the present invention. The circuit configuration diagram of the station, Figure 1D, Figure 1E, and Figure 1 are circuit diagrams showing other embodiments of the mobile radio used in the system of the present invention, and Figure 1G is shown in Figure 1F. Figure 1H is a detailed circuit diagram of a radio transmitter circuit which is a component of the circuit shown in Figure 1F, and Figure 11 is a detailed circuit diagram of a radio receiver circuit which is a component of the circuit shown in Figure 1F. FIG. 1 is a circuit configuration diagram showing another embodiment of the wireless base station used in the system of the present invention, and FIG. 2A is a time slot diagram for explaining the time slots used in the system of the present invention. A slot structure diagram; FIG. 2B is a diagram showing a radio signal waveform of a time slot; FIG. 2C is a time slot structure diagram for explaining another embodiment of a time slot used in the system of the present invention; FIG. 2D is a permissible increase amount diagram showing the permissible increase amount of modulation deviation used in the system of the present invention, FIGS. 3A and 3B are spectral diagrams showing the spectra of speech signals and control signals, and FIG. 3C is FIG. 3D is a spectrum diagram showing the spectra of the CM signal and FDM signal; FIGS. 4A and 4B are flow diagrams showing the operation flow of the system according to the present invention. Figure 5 is a spectrum diagram of a frequency division multiplexed signal, Figure 6A is an amplitude diagram showing changes in amplitude of a time division time compression multiplexed signal, Figures 6B, 6C, and 6D are time diagrams. A sampling diagram showing how the divided time compression multiplexed signal is sampled, Figure 7 is a specification diagram showing the specifications of various systems, and Figure 8 explains the time slots used by the system shown in Figure 7. Figures 9A and 9B are characteristic diagrams showing the input/output characteristics of the amplifier, and Figure 10 shows the relationship between the multiple load gain of the time division time compression multiplexed signal and the multiplex number of the audio signal. Diagrams showing the relationship, Figures 11 and 1
FIG. 2 is a multiple load gain diagram showing the relationship between the multiple load gain of a frequency division multiplexed signal and the number of communication paths, cited from a known document. 10... Telephone network 20... Gateway switchboard 22
-1 to 22-n...Communication signal 30...Radio base station 31...Signal processing section 20 32...Wireless transmitting circuit 35...Radio receiving circuit 3
8... Signal speed restoration circuit group 38-1 to 38-n... Transmission speed restoration circuit 39...
Signal selection circuit group 39-1 to 39-n...Signal selection circuit 40...Control unit 41...Clock generator 42...Timing generation circuit 51...Signal speed conversion circuit group 51-1... 51-n...Signal speed conversion circuit 52...
Signal assignment circuit groups 52-1 to 52-n...Signal assignment circuit 71...Compressor (group) 72...Expander (group>) 73.74...FDM channel converter 91...Digital Encoding circuit 92...Multiple conversion circuit 100.100-1 to 100-n-...Mobile radio device 10
1... Telephone unit 118-1, 118-2... Switch 120... Reference crystal oscillator 2 2 2 3 3 3 3 3 7 7 1 1 1 1 1-1, 121-2... Synthesizer 2 -1.122
-2...Switch 3...Transmission/reception intermittent controller 1...Speed conversion circuit 2...Wireless transmission circuit 133...Transmission mixer 4...
- Transmission unit 135... Radio receiving circuit 6... Reception mixer 137... Receiving unit 8... Speed recovery circuit 141... Clock regenerator. 1... Compressor 172... Expander 3.
174...FDM channel converter 1...Amplifier 212...Frequency discriminator 3.
...Digital/analog signal separator 4...Bandpass filter 216...Modulator 7...Digital/analog signal mixer.

Claims (1)

[Claims] 1. Each radio base means (30) each covering a plurality of zones to constitute a service area, and a radio base means (30) for moving across the plurality of zones and communicating with the radio base means; barrier exchange means (20) for exchanging communications with each mobile radio means (100) using a radio channel carrying time-compressed delimited signals in time slots of a frame structure; In mobile communication methods,
The level of the radio signal used for communication between the radio base means and the mobile radio means is determined based on the multiple load gain obtained by the time-compressed segmented signals, and the signal to be transmitted is transmitted through a compressor. Means (71, 171
), the amplitude distribution is compressed to a desired range and transmitted, and the received signal is restored to the original amplitude distribution by the expander means (72, 172), and the frequency band of the temporally compressed and segmented signal is A time division communication method for mobile communication in which a signal other than the temporally compressed segmented signal is placed in a lower frequency band. 2. Each radio base means (30) each covering a plurality of zones to constitute a service area, and a time frame structure for moving across said plurality of zones and communicating with said radio base means. In a mobile communication system using a barrier exchange means (20) for exchanging communication between each mobile radio means (100) using a radio channel carrying temporally compressed and delimited signals in slots. , the radio base means and the mobile radio means determine their respective transmission output levels based on the multiple load gain obtained by the time-compressed segmented signals, and adjust the amplitude distribution of the signals to be transmitted to a desired value. Compressor means (71, 171) for compressing the received signal into a range and transmitting it, and expander means (72, 172) for restoring the received signal to the amplitude distribution before compression.
and uncompressed signal communication means (73, 74, 173, 174, 118-1,
118-2). A time division communication system for mobile communication comprising: