JPH06232833A - Communication method for tdma system and transmitter/ receiver for its device - Google Patents

Abstract

PURPOSE:To increase the amount of information to be transmitted at every time slot by generating the lump data of one bit, at least, corresponding to a lump time part and cotrolling the level of the transmitting output of the lump data corresponding to the phase change of the lump time part. CONSTITUTION:A ROM 3 is provided with the terminal of totally (n+3) bits of (n) bits corresponding to (n) symbols, lump select bit (RS), up-down bit (UD) and phase selection bit (PS) for designating the read address. Concerning data stored in the ROM 3, the reading output is D/A converted 4 and provided with a previously calculated value so as to modulate the phase of a carrier wave inputted to a modulator 6 with a voltage value removing the higher harmonic wave as prescribed. In this case, the lump data of one bit at least are transmitted from the transmission side corresponding to whether the phase of a change characteristic at the lump part of the time slot is changed in the middle or not.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a TDMA type communication method using a ramp time section for information transmission and a transceiver of the communication device.

[0002]

2. Description of the Related Art In mobile communication such as a car phone and a mobile phone, an FDMA (Frequency Division Multiple Access) which divides a plurality of pieces of information into frequency bands and multiplexes them for transmission.
Instead of the method, TDMA (Time Division Mult) suitable for the transmission of digital information as the amount of transmission increases.
iple Access: Time-division multiplex connection) system has been increasing. The TDMA method is a method of transmitting a plurality of pieces of information by dividing the information in units of time. In the time slot assigned to the user, the output of the transmission power amplifier is increased at a specified timing as shown in the waveform shown in FIG. Decrease is done after time. FIG. 1 shows a quadruple TDMA method, and one piece of information is divided and transmitted at each position where the slot numbers are the same. As shown in FIG. 2, in each time slot, the ramp time part before the output gradually increases from the reference level to the predetermined level (rising), the information time part for transmitting information, and the output gradually decreases to the reference level. A trailing (falling) ramp time portion is provided, and a guard time portion is provided so that the waveforms of the next adjacent time slots do not overlap with each other due to a synchronization shift or the like. However, it is impossible to increase the output of the power amplifier sharply, so
As shown in FIG. 3, it is specified that the output waveform A should change within the range surrounded by the diagonal lines.

[0003]

By the way, since the information transmission amount by the information time portion for each time slot is set, it is difficult to increase the information transmission amount of the information time portion. However, it is desired to transmit a lot of information even with one bit. Therefore,
An object of the present invention is to provide a TDMA communication method capable of increasing the amount of information transmission for each time slot and a transceiver of the apparatus.

[0004]

According to the communication method of the TDMA method of the present invention, information is transmitted in a time slot unit having a ramp time section for raising and lowering a transmission output before and after an information time section carrying information. A time-division multiplex connection type communication method for generating at least 1-bit ramp data for a ramp time portion, controlling the transmission output level by making the ramp data correspond to the phase change of the ramp time portion, and transmitting the data. It is characterized in that the phase change characteristic of the ramp time portion is detected from the received signal level obtained by receiving the output, the detected phase characteristic is discriminated, and the ramp data is obtained according to the discrimination result.

A transmitter of a TDMA communication apparatus according to the present invention transmits information in a time slot unit having a ramp time section for raising and lowering a transmission output before and after an information time section for carrying information. A transmitter of a communication device of a multiplex connection system, wherein a means for generating at least 1-bit ramp data for a ramp time section and a transmission output level are controlled by making the ramp data correspond to a phase change of the ramp time section. And means.

The receiver of the TDMA communication apparatus of the present invention transmits information in units of time slots having ramp time portions for raising and lowering the transmission output before and after the information time portion for carrying information, and transmits the information. At this time, generate at least 1-bit ramp data for the ramp time part,
A receiver of a communication apparatus of a time division multiplex connection system, which controls a level of a transmission output by correlating lamp data with a phase change of the ramp time part, wherein a lamp is generated from a reception signal level obtained by receiving the transmission output. It is characterized in that it has a detecting means for detecting the phase change characteristic of the time portion, a discriminating means for discriminating the detected phase characteristic, and a means for obtaining the ramp data according to the discrimination result of the discriminating means.

[0007]

According to the present invention, at least one bit of ramp data is transmitted from the transmitting side depending on whether or not the phase of the change characteristic of the ramp time portion of the time slot is changed on the way, and the receiving side receives the ramp time from the received signal. The ramp data can be obtained by detecting the change characteristic of the portion and determining whether or not the detected characteristic has a phase change.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. In this embodiment, the present invention is applied to a binary phase modulation / demodulation system. First, FIG.
In the transmitter of the TDMA communication apparatus according to the present invention shown in FIG. 1, digital data as information to be transmitted is issued from the CPU 1 in synchronization with a predetermined timing and supplied to the shift register 2. The shift register 2 converts serial digital data supplied from the CPU 1 into n-bit parallel data. A ROM 3 is connected to the parallel data output of the shift register 2.

The ROM 3 is used to specify a read address.
n bits corresponding to n symbols, a ramp select bit (RS) that distinguishes whether the data at this time is an information time part or a ramp time part, and if it is a ramp time part, distinguish whether it is a rising edge or a falling edge It has a total of n + 3 bits of up / down bits (UD) to be turned on and a phase select bit (PS) for whether to shift the phase in the ramp time part. In the ROM 3, for example, a value calculated so that the phase-modulated wave shown in FIG. 5 appears at the output of the power amplifier is stored corresponding to the address. In this embodiment, since the output of the ROM 3 is connected to the D / A converter 4 for M bits, this RO
M3 requires a maximum capacity of 2 ^{(n + 3)} × M bits.

The read output from the ROM 3 is the D / A converter 4
Is converted into an analog signal. The D / A converter 4 uses L in order to attenuate a harmonic signal that is more than twice the conversion speed.
A PF (low pass filter) 5 is connected. LPF
The output signal from 5 is input to the baseband input terminal of the modulator 6. The modulator 6 is realized by, for example, a ring modulator, and its carrier wave input section is connected to the local oscillator 9. The carrier wave inputted from the local oscillator 9 is phase-modulated by the signal inputted to the baseband input terminal. The output of the two-phase phase modulated wave output from the output terminal of the modulator 6 is amplified by a PA (power amplifier) 7 and emitted from the antenna 8 into the air.

The power sources of the modulator 6 and the PA 7 are turned off by the CPU 1 via the power control signal (PC) except when the slot is in use. The mechanism of phase shift in the ramp time portion, which is a feature of the present invention, will be described with reference to the waveforms in FIG. As described above, the read output of the data stored in the ROM 3 is D / A converted,
It has a value calculated in advance so that the carrier wave input to the modulator 6 is phase-modulated as shown in FIG. 5 at the voltage value after the harmonic components are removed.

First, the power of the modulator 6 is turned off except when in use.
Therefore, the output from the modulator 6 can be considered to be almost zero, and therefore, it is acceptable. Next, the RS bit and the UP bit are set to "1" in the rising ramp time portion, and "1" is sent from the CPU to the transmission digital input. At this time, PS remains "0". Since these values are the addresses to the ROM3, the local oscillator so that the waveform corresponding to this address, which has the phase "0" in the rising ramp time portion of FIG. The values for phase-modulating the carrier waves from 9 are stored. Next, when the output of PA3 is set to a predetermined amplitude value, for example, a value 30 dB higher than that at the time of power off, and the CPU 1 sets the PS bit to "1", the phase is set to "1" in the rising ramp time portion of FIG. Stored are the values that phase modulate the carrier from the local oscillator 9 so that the corresponding waveform appears on PA7.
In the next information time part, CPU1 or RS bit
Since it is set to "0", the output of the ROM 3 is not affected by the values of the UP bit and the PS bit, and is exclusively determined by the value from the shift register 2. The operation of the transmitter in the information time section is similar to that of the analog system using the conventional two-phase phase modulation system.

Next, in the receiver in the TDMA type communication apparatus according to the present invention, as shown in FIG. 6, the modulated signal received by the antenna 11 has an unnecessary wave removed by a BPF (band pass filter) 12, After being amplified by the LNA (low noise amplifier) 13, it is input to the modulation signal input terminal of the phase detector 15 and also input to the delay circuit 14.

The delay circuit 14 is delayed by one symbol rate time, and its output is input to the delay modulation signal input terminal of the phase detector 15. In the phase detector 15, the current modulation signal input is compared with the modulation signal delayed by the one symbol rate time, and the voltage value corresponding to the phase shift is output from the phase change output terminal. The phase detector 15 may be, for example, two balanced transformers 15 as shown in FIG.
1, 152 and a ring modulator composed of four diodes 153 to 156.

Since the detection output from the phase detector 15 has a baseband waveform, this is detected by the timing extraction circuit 1
When the eyeband of the baseband wave is input to 6, the timing pulse that can determine “1” / “0” of the baseband waveform is extracted and output to the determination circuit 17. The timing extraction circuit 16 is a DPLL
This can be easily realized by using a (digital phase lock loop) IC. In the comparator 18, LN
By comparing the output level of A13 with a predetermined value Vr, an amplitude value that may cause phase shift during the ramp time portion in the transmitter, for example, when the input is 30 dB larger than that at power-off, the value is detected. , To the timing extraction circuit 16.

The timing extraction circuit 16 extracts and sends the first timing pulse from the baseband waveform as described above, and when a certain time has elapsed after the amplitude value was detected by the comparator 18, for example, at half the symbol rate. When the time has passed, the second timing pulse is transmitted. In the decision circuit 17, the baseband signal demodulated by the phase detector 15 is sent to the eye pattern of each symbol in the information time part most immediately after the amplitude value detected by the comparator 18 in the ramp time part. When opened, the received sample is judged as "1" / "0" and used as a received digital signal. The determination circuit 17 includes, for example, as shown in FIG. 8, a comparator 171 that compares the phase detection output with a reference value V _rr , an OR circuit 172 that takes the logical sum of the first and second timing pulses, and an OR circuit 172. It is composed of a D flip-flop 173 which holds and outputs the output signal of the comparator 171 according to the output timing pulse.

The received digital signal is a conventional TDMA signal.
Information is added at least 1 bit each before and after each used slot as compared with that obtained by the method.

[0018]

As described above, according to the present invention, at least 1-bit ramp data is transmitted from the transmitting side and the receiving side depending on whether or not the phase of the change characteristic of the ramp time portion of the time slot is changed midway. Then, the ramp data can be obtained by detecting the change characteristic of the ramp time portion from the received signal and determining whether or not the detected characteristic has a phase change. Therefore, the data before and after the information time portion of one time slot can be obtained. Each can be added. Therefore, since the lamp data can be added, it can be used, for example, as information indicating whether the information time part is control information or communication information for performing communication, which makes it possible to detect the time slot of the control information quickly. Can be Further, it is possible to use the lamp data as the alarm signal when the received electric field strength during communication falls below a predetermined value.

[Brief description of drawings]

FIG. 1 is a diagram showing a quadruple TDMA method.

FIG. 2 is a diagram showing a configuration of one time slot.

FIG. 3 is a diagram showing a waveform change allowable range of a time slot.

FIG. 4 is a block diagram showing a transmitter of a TDMA communication apparatus according to the present invention.

FIG. 5 is a diagram showing a rising characteristic in which a phase is changed in a ramp time portion.

FIG. 6 is a block diagram showing a receiver of a TDMA communication device according to the present invention.

7 is a block diagram showing a configuration of a phase detector in the receiver of FIG.

8 is a block diagram showing a configuration of a decision circuit in the receiver of FIG.

[Explanation of symbols for main parts]

 1 CPU 3 ROM 6 Modulator 7 Power Amplifier for Transmission 16 Timing Extraction Circuit 17 Judgment Circuit

Claims (3)

[Claims] 1. A time division multiplexing connection type communication method for transmitting information in a time slot unit having a ramp time section for raising and lowering a transmission output before and after an information time section carrying information. A reception signal obtained by generating at least 1-bit ramp data for the ramp time portion, controlling the level of the transmission output by making the ramp data correspond to the phase change of the ramp time portion, and receiving the transmission output. A communication method characterized in that the phase change characteristic of the ramp time portion is detected from a level, the detected phase characteristic is discriminated, and the lamp data is obtained according to the discrimination result. 2. A transmitter of a communication apparatus of a time division multiplex connection system for transmitting information in a time slot unit having a ramp time portion for raising and lowering a transmission output before and after an information time portion for carrying information. And a means for generating at least 1-bit ramp data for the ramp time portion, and a means for controlling the level of the transmission output by making the ramp data correspond to a phase change of the ramp time portion. And a transmitter. 3. Information is transmitted in a time slot unit having a ramp time portion for raising and lowering a transmission output before and after an information time portion for carrying information, in which case at least one bit for the ramp time portion is transmitted. A receiver of a communication device of a time division multiplex connection system that generates ramp data and controls the level of the transmission output by making the ramp data correspond to a phase change of the ramp time part,
Detecting means for detecting the phase change characteristic of the ramp time portion from the received signal level obtained by receiving the transmission output, discriminating means for discriminating the detected phase characteristic, and the lamp according to the discrimination result of the discriminating means. A receiver having means for obtaining data.