JPH1051428A - Diversity control method - Google Patents

Abstract

(57) [Problem] A conventional post-detection diversity control system of the TDMA system requires complicated control of the boundary timing of a burst to be selected for each slot, so that the circuit becomes complicated. A plurality of receiving units independently process audio data, and synthesize the audio data processed by the plurality of receiving units, thereby making switching control unnecessary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diversity control method for a digital and TDMA radio apparatus.

[0002]

2. Description of the Related Art The conventional post-detection diversity control method is as follows.
As shown in FIG. 2, signals input from antennas 1A and 1B are converted into intermediate frequencies (IF) by respective radio units 2A and 2B, and demodulated units 3A and 3B and TDMA.
The data is converted into continuous digital audio data (PCM audio data) of each reception slot by the synchronization control units 4A and 4B.

[0003] In the radio units 2A and 2B, audio data is multiplexed in a time division manner and is in a burst form. FIG. 3 shows T
Receive slots RX1, 2, 3, 4 in the DMA / TDD system
2 shows the timing at which the time-division multiplexed signal of FIG. The burst configuration includes a preamble a, a unique word b, control information c, user information (speech information) d, and a CRC in a PHS communication channel as an example.
It consists of a check bit e. When the radio units 2A and 2B receive radio waves from the antennas 1A and 1B, RX1 and RX2 shown in FIG.
Each of the receiving slots indicated by 2, 3, and 4 is a burst signal, and the signals of these RX 1, 2, 3, and 4 receiving slots are converted into IF signals, and then demodulated by the demodulation units 3A and 3B and subjected to ADPCM. Each is converted into PCM data by decoding.

[0004] The TDMA synchronization control units 4A and 4B synchronize the audio data of each reception slot and continuously output the audio data. The diversity control unit C determines the best slot among the TDMA slots based on the received radio field intensity RSSI value detected by these two reception units and the presence or absence of a CRC error detected based on the CRC check bit for each TDMA slot. And outputs a selection signal to the selection section D to output only the PCM audio data of the selected slot.

[0005]

SUMMARY OF THE INVENTION However, TDM
Since the PCM audio data output from the A synchronization control units 4A and 4B is continuous data, the diversity control unit C must accurately control the burst boundary timing of each of the A-system and B-system reception slots for each slot. . Therefore, the circuit configuration of the diversity control unit C becomes complicated.

It is an object of the present invention to solve the problems of the prior art and to provide a diversity control system having a simple configuration.

[0007]

According to the present invention, in a diversity control system for a digital and TDMA radio apparatus, a plurality of receiving sections for continuously outputting voice data in a plurality of receiving slots are provided. A receiving unit configured to determine whether the quality of voice data satisfies a predetermined criterion for each reception slot; and the quality determination unit satisfies a predetermined criterion in voice data of each reception slot that is continuously output. A diversity control system, comprising: a clamp unit that allows audio data to pass only in the slot determined to be present; and a synthesizing unit that synthesizes audio data output by the clamp units of the plurality of receiving units. .

[0008]

FIG. 1 is a block diagram of a diversity control circuit according to an embodiment of the present invention. First, antenna 1A, radio section 2A, demodulator 3A, TDMA synchronization control section 4A, control section 5A, clamp circuit (AND gate) 6
The A-system receiving unit composed of A will be described. The high-frequency signal input from the antenna 1A is converted into an intermediate frequency (IF) by the radio unit 2A, and demodulated by the demodulator 3A into demodulated data including not only user information (voice data) but also unique words for each TDMA reception slot. Convert this to TDM
The A-synchronization control section 4A synchronizes and outputs the PCM audio data of each reception slot so that the data is continuously output.

Due to fading, the received signal strength RSS
When I becomes weak, a transmission error occurs in the demodulated data and noise is generated.
I and CRC errors (based on CRC check bits)
Is detected. Based on this detection, the control unit 5A determines whether the signal quality satisfies a predetermined criterion (the RSSI is equal to or higher than a predetermined level and there is no CRC error) for each reception slot, and a clamp circuit (AND gate) 6A Only the PCM audio data of the reception slot satisfying the predetermined criterion is clamped and passed at the boundary timing, and the other data is not transmitted to the subsequent stage. The receiving section of the B-system including the antenna 1B to the clamp circuit 6B has the same configuration as the above-described A-system.

The clamp circuits 6 of the above-mentioned A system and B system
A, PC of each receiving slot sequentially output after passing through 6B
The M audio data is synthesized by a synthesis circuit (OR gate) 7. Since the digital audio signals of the receiving slots sequentially output from the A-system and B-system clamping circuits 6A and 6B satisfy the signal quality of the predetermined reference received by both receiving units A and B, the synthesizing circuit 7 , The best digital audio signal (PCM data) is obtained.

[0011]

As described above, according to the present invention, in each receiving section, only the audio data of the receiving slot satisfying the quality standard is clamped and passed, and the audio data output from each receiving section is synthesized. Therefore, each receiving unit can easily control the timing of the receiving slot and the audio data, and the configuration of the control circuit is simplified.

[Brief description of the drawings]

FIG. 1 is a diversity control block diagram showing an embodiment of the present invention.

FIG. 2 is a diversity control block diagram showing a conventional example.

FIG. 3 is a timing chart of a received signal and PCM data for explaining a conventional example.

[Explanation of symbols]

 A: A system receiving unit B: B system receiving unit 1A, 1B: Antenna 2A, 2B: Radio unit 3A, 3B: Demodulator 4A, 4B: TDMA synchronization control unit 5A, 5B: Control unit 6A, 6B: Clamp circuit ( 7: Synthesis circuit (OR gate)

Claims (1)

[Claims] 1. A diversity control system for a digital and TDMA wireless device, comprising: a plurality of receiving units for continuously outputting voice data in a plurality of receiving slots, wherein each of the plurality of receiving units is provided for each receiving slot. A quality determining unit that determines whether or not the quality of the audio data satisfies a predetermined criterion, and among the audio data of each reception slot that is continuously output, only the slot that the quality determining unit determines that the predetermined criterion is satisfied is used. A diversity control method, comprising: a clamp unit for passing the signal; and a synthesizing unit for synthesizing audio data output from the clamp units of the plurality of receiving units.