JPS63254837A - Radio communication equipment - Google Patents

Abstract

PURPOSE:To attain ease and highly accurate monitor for communication quality without complicating the circuitry by judging the communication quality depending on the degree of discrepancy between quality monitor data for reception communication and a prescribed data for communication quality monitor. CONSTITUTION:The output of a microphone amplifier 4 is sent to a superimposing circuit 15 via a BPF (100Hz-10 and several kHz)14 and the communication quality monitor data being a prescribed value of an M series code is sent to the circuit 15 via an LPF 15. The circuit 15 applies frequency multiplex to both inputs and sends it to a modulator 5 and the signal subjected to FM modulation is sent from an antenna 8. Moreover, the reception signal is subjected to FM demodulation 10 and the reception communication quality data is fed to the CPU 12 via the LPF 18. The CPU 12 compares the reception signal communication quality monitor data with a prescribed communication quality monitor data as the phase and duty ratio, and the channel is switched when the error rate is within a prescribed range.

Description

[Detailed description of the invention] The present invention will be described in the following order.

A. Industrial field of application B0 Overview of the invention C9 Background art [Figures 2 and 3] D0 Problems to be solved by the invention E0 Means for solving the problems F0 Effects G, Examples [First [Figure] H0 Effects of the Invention (A. Field of Industrial Application) The present invention relates to eight wireless communication devices, and particularly to a wireless communication device that can monitor the quality of calls.

(B. Summary of the Invention) The present invention is intended to enable easy and fine-grained monitoring of speech quality in a wireless communication device without unnecessarily complicating the circuit configuration. Out-of-band predetermined call quality monitoring data is frequency-multiplexed and transmitted, and the other party's wireless communication device frequency-multiplexes the voice signal and the predetermined call quality monitoring data after receiving them, and then separates them. Then, the received call quality monitoring data is compared with predetermined call quality monitoring data, and the call quality is determined based on the degree of discrepancy.

(C, Background Art) [Figures 2 and 3] In a cordless telephone communication system, each wireless communication device using the system does not occupy a unique frequency as its own transmission frequency, but all wireless communication A large number of channels (for example, 46) are shared, and when actually communicating, an empty channel is searched from among the large number of shared channels, and communication is performed with the other party through that channel. A wireless communication method using such a system has been proposed by the applicant company in Japanese Patent Application No. 61-227349.

FIG. 2 shows one example of a wireless communication device used in such a system.

In the figure, 1 is a handset section, 2 is a microphone built into the handset section 1, and 3 is a speaker. 4 is a microphone amplifier that amplifies the output signal of the microphone 2; 5 is a modulator that converts the output signal of the microphone amplifier 4 into FM; and 6 is a transmitter for transmitting the modulated signal 13 from the modulator 5. A circuit 7 is a duplexer that transmits the output signal of the transmitting circuit 6 to the antenna 8 and transmits the signal received by the antenna 8 to the receiving circuit 9. 10 is a demodulator that demodulates the FM modulated signal received by the receiving circuit 9; 11 is a speaker amplifier that amplifies the No. 15 signal demodulated by the demodulator 10 and sends it to the speaker 3; 12 is a system control device for the communication device. The CPU sends a muting signal to the microphone amplifier 4 to apply muting, and sends frequency specification data to the channel control synthesizer 13 to specify the frequency used for communication.

By the way, in a cordless telephone, the quality of the call may change during a call, and in some cases, the call may become impossible.

Therefore, if the call quality deteriorates during a call, it is necessary to be able to recover the call quality by switching the call channel, and it is necessary to automatically recover the call quality by switching the call channel. Wireless communication devices are required to have functions that can perform these functions.

Incidentally, FIG. 3 shows a part of the procedure for selecting, transmitting, and receiving radio wave frequencies used by a land mobile station that performs cordless telephone communication as stipulated by the Radio Equipment Regulations. As is clear from this figure, if the dead state continues for 10 seconds during a call operation, the standby operation must be started.

Additionally, if the interference continues for more than 5 seconds, the communication channel must be changed, and if the interference continues for more than 15 seconds, the phone must enter standby mode.

By the way, call quality has conventionally been monitored by detecting interference and received field strength using separate detection circuits, and the detection result is given a +1 [to determine whether or not there is an insensitive state or not, and whether or not it is in an interference state. I was deciding whether it was there or not.

(D. Problems to be Solved by the Invention) By the way, communication quality is originally degraded not only by a decrease in received field strength and interference by other carriers, but also by multipath and fading. Decrease in received field strength and interference from other carriers can be detected in the past (11), but it is very difficult to detect multipath and fading, and the quality of communication due to multipath and fading is low. In many cases, monitoring was not possible.

Furthermore, although it has been possible to detect a decrease in received field strength and interference in the past, it has been necessary to separately provide a received field strength detection circuit and an interference detection circuit.

This inevitably led to an increase in the number of parts, which led to larger and more expensive wireless communication devices.

The present invention has been made in order to solve these problems, and it is an object of the present invention to make it possible to detect with high precision the deterioration in call quality caused by any factor without making the device unnecessarily complicated. With the goal.

(E. Means for Solving the Problems) In order to solve the above problems, the wireless communication device of the present invention frequency-multiplexes audio signals and predetermined call quality monitoring data outside the band. Then, after receiving and separating the voice signal and call quality monitoring data transmitted by frequency multiplexing from the other party's wireless communication device, the received call quality monitoring data is combined with predetermined call quality monitoring data. The feature is that the call quality is determined based on the degree of discrepancy by comparison.

(F. Effect) According to the wireless communication device of the present invention, predetermined digital call quality monitoring data is frequency-multiplexed with the voice signal and transmitted, and the frequency-multiplexed voice signal and the call quality monitoring data are transmitted. After receiving, it is separated and the received call quality monitoring data is not detected to see if it is as predetermined. It is possible to accurately grasp the call quality. In other words, if the call quality deteriorates regardless of the cause, the call quality monitoring data sent from the other party's wireless communication device will naturally no longer be as predetermined, and the phase and duty ratio will become incorrect.
By comparing the received call quality monitoring data with predetermined call quality monitoring data, it is possible to detect whether or not the call quality has deteriorated and to what extent.

(G. Embodiment) [FIG. 1] Hereinafter, the wireless communication device of the present invention will be described in detail according to the illustrated embodiment.

FIG. 1 is a circuit block diagram showing one embodiment of the wireless communication device of the present invention.

In this figure, the same parts as in FIG. 2 are given the same reference numerals, detailed explanations are omitted, and only different parts will be explained in detail.

Reference numeral 14 denotes a bandpass filter that passes audio signals in a band of 100H2 to 10-odd KHz, which receives the output signal of the microphone amplifier 4 and sends the signal to the superimposition circuit 15. 16 is C
This is a low-pass filter that cuts frequency components of 100 Hz or more of predetermined call quality monitoring data of 200 bps, which is an M-sequence code generated by the PU 12, and sends it to the superimposition circuit 15. The superimposition circuit 15 receives the audio signal from the bandpass filter 13 and the lowpass filter 16.
and predetermined call quality monitoring data are frequency multiplexed and sent to the modulator 5. Then, the output signal of the superimposition circuit 15 is subjected to FM modulation in the modulator 5, and this FM signal is transmitted from the antenna 8.

Reference numeral 17 denotes a band-pass filter that passes signals in a band of 100 Hz to 10-odd KHz, and is inserted between the demosimulator 10 and the speaker amplifier 11. Reference numeral 18 denotes a low-pass filter that extracts received call quality monitoring data that passes signals in the frequency band below Hz from the output of the demosimulator 10 (ffi number to ioo), and sends the extracted received call quality monitoring data to the CPU 12.

The CPU 12 of this embodiment is the CPU 12 of a conventional wireless communication device.
In addition to the above operations, the above-mentioned communication quality monitoring data determined in advance is created and sent to the superimposition circuit 15 via the low-pass filter 16, and the received communication quality monitoring data is sent via the low-pass filter 18. This received call quality monitoring data is compared with the predetermined call quality monitoring data in terms of phase and duty ratio, the error rate is calculated, and if the error rate is within a predetermined range, the call channel is switched. Perform actions, etc.

According to such a wireless communication device, since predetermined digital call-carrying monitoring data is frequency-multiplexed into voice (no. It is possible to evaluate the call quality by checking whether the received call quality monitoring data is the same as predetermined data and determining the error rate.Also, it is possible to evaluate the call quality by determining the error rate. After receiving the call quality type current data and voice signal, the data for monitoring the received call quality is compared with a predetermined data, and the error rate is determined to determine the call quality. When the error rate reaches a certain level, the call quality is evaluated to be on the same level as the above-mentioned call interference state, and the call channel is switched. When the error rate reaches a certain level, which is even higher than that level, the call quality is considered to be the same as the call interference state. It is possible to evaluate the call quality as "1-" and enter the standby state.

This received call quality monitoring data is then compared with predetermined data and the degree of deterioration in call quality is determined from the error rate. It is possible to detect with high accuracy regardless of whether there is a decrease in the carrier, interference by other carriers, multipath, or facing.

Moreover, with this wireless communication device, by adding multiple filters and superimposing circuits, and simply changing the effective program of the CPU 12, it is possible to detect degradation in call quality due to any cause with a high degree of granularity. No special circuit is required.

Therefore, communication quality can be monitored without unnecessarily complicating the circuit configuration, and a high-performance, compact wireless communication device can be provided at a low price.

(H. Effects of the Invention) As described above, the wireless communication device of the present invention provides a transmission ( g system, a receiving system that receives the frequency-multiplexed audio signal and predetermined call quality monitoring data, and separates the frequency-multiplexed audio signal and the call quality monitoring data after receiving; A call quality monitoring means that compares the received call quality monitoring data with predetermined call quality monitoring data and determines the call quality based on the degree of discrepancy;
It is characterized by having the following.

Therefore, according to the wireless communication device of the present invention, predetermined digital call quality monitoring data is frequency-multiplexed with the voice signal and transmitted, and the frequency-multiplexed voice signal and the call quality monitoring data are received and separated. The received call quality monitoring data is compared with predetermined call quality monitoring data to detect whether it is as per the predetermined data, so the call quality is determined based on the comparison result. Can be accurately grasped.

[Brief explanation of the drawing]

Fig. 1 is a circuit block diagram showing one embodiment of the wireless communication device of the present invention, Fig. 2 is a circuit block diagram showing a conventional example of the wireless communication device, and Fig. 3 is a circuit block diagram showing the conditions for cordless telephone communication. FIG. 3 is a diagram showing a part of the procedure for selecting the frequency of radio waves to be used, and for transmitting and receiving the radio waves. Explanation of symbols 2.4.14.15.16.5.6...Transmission A-3 system, 9.10.11.3...Reception system, 17.18...Signal separation filter, 12... Call quality monitoring means.

Claims (1)

[Claims] (1) A transmission system that frequency-multiplexes an audio signal and predetermined call quality monitoring data that occupies a frequency band outside the frequency band of the audio signal, and transmits the frequency-multiplexed audio signal and a reception system that receives predetermined call quality monitoring data and separates the frequency-multiplexed voice signal from the call quality monitoring data after reception; A wireless communication device comprising: a call quality monitoring means for comparing the quality monitoring data and determining the call quality based on the degree of discrepancy.