JPH0661938A - Radio telephone set - Google Patents

Abstract

PURPOSE:To prevent a user from getting confused even in a circuit cut-off (no sound) state by letting the user previously perceive the possibility of the circuit cut-off state in a busy mode of a portable telephone set. CONSTITUTION:This radio telephone set consists of a reception circuit 1 which receives a modulated signal and outputs an intermediate frequency signal, a reference signal oscillator 3, a circuit quality detecting circuit 2 which calculates the circuit quality based on the reference signal and the intermediate frequency signal, a demodulated signal receiving circuit 4 which outputs the deterioration of the quality of a radio circuit as a warning tone or superposes this tone based on the detecting result of the circuit 2, an SP CODEC (voice coder/ decoder) 5, and a receiver 6. Then a fact that the circuit may possibly be cut (no sound) in a busy mode due to the deterioration of the circuit quality is informed to a user by a warning tone.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio telephone, and more particularly to a digital communication radio telephone.

[0002]

2. Description of the Related Art Conventionally, a code decoder (CODEC) having a function of converting a voice (analog signal) into a digital signal or a digital signal into a voice (analog signal) is used in this type of radio telephone. ing. For this code decoder (CODEC), a method of coding an instantaneous voltage at a sample time point (PCM method), a method of coding a difference at each sample time point (ΔM method), and the like have been used. However, in recent years, a voice coder / decoder (hereinafter, SP CODEC) that encodes only a voice signal and only a characteristic component of the voice signal has been used.

FIG. 4 shows an example of the configuration of a conventional digital communication type wireless telephone.

In FIG. 4, a receiving circuit 9 receives a modulated signal of a communication radio wave, performs frequency conversion and demodulation, and outputs a received data signal 9-1. The demodulation signal reception circuit 12 receives the reception data signal 9-1 and outputs the decoded voice signal to SP C.
Output to ODEC5. The SPCODEC 5 decodes the digital signal output from the demodulation signal circuit 12, converts it into an analog signal, and then outputs it to the receiver 6 as an audible signal.

[0005]

When the PCM CODEC system is used, this conventional radio telephone set has a correlation between a signal error and a decoded waveform, so that the PCM CODEC is used.
Since the user of the wireless telephone adopting the above can hear the deterioration of the wireless line quality by ear, the user can choose to hold the call or end the call depending on the deterioration.

However, in recent years, for the purpose of lowering the transmission rate in the wireless section and narrowing the occupied bandwidth for modulation, a speech code decoder (SP) that encodes only the speech signal for transmission information and further only the characteristic component of the speech signal. When CODEC) is used in a wireless telephone, the voice reproducibility after decoding may be extremely deteriorated when a code error occurs in the wireless line because the signal compression rate is high, and therefore, in general, this kind of When SP CODEC is adopted, a method has been adopted in which error detection and correction codes are added to the encoder data output to ensure the quality of the transmission path.

In general, since the error detection capability is higher than the correction capability, if the signal error on the transmission path is within the correction capability, the correctly corrected signal is input to the decoder, but the signal error increases. In that case, only the error detection function works, the defective code is discarded and is not input to the decoder, or the demodulation output signal is muted and stopped.

Therefore, in the conventional wireless telephone, when the quality of the wireless line deteriorates, the user can hear a completely normal voice up to a certain deterioration state, but when the number of errors further increases, the line is suddenly changed. There is a problem in that the user is confused and uncomfortable because it becomes a disconnected (silent) state.

[0009]

A radio telephone according to the first aspect of the present invention comprises a receiving circuit for receiving and demodulating a modulated signal of a communication radio wave, and a reference signal oscillator for oscillating a reference signal. Line quality detecting means for calculating the line quality from the fluctuation of the phase difference between the output of the reference oscillator and the reference signal from the reference oscillator, and a line for receiving the demodulated signal of communication from the receiving circuit and outputting from the line quality detecting means. Warning sound signal data output means for outputting warning sound signal data when the quality information signal falls below a predetermined value, and warning sound output for decoding and converting the warning sound signal data into an analog signal and outputting a warning sound. And means.

A radio telephone according to the second aspect of the present invention includes a receiving circuit for receiving and demodulating a modulated signal of a communication radio wave and outputting an electric field strength signal proportional to the electric field strength of the modulated signal, and the receiving circuit. Warning sound signal data output means for receiving a demodulated signal of communication and outputting warning sound signal data when the electric field strength signal falls below a predetermined electric field strength value, and decoding the warning sound signal data into an analog signal And a warning sound output means for converting and outputting a warning sound.

The radio telephone according to the third aspect of the invention oscillates a reference signal and a receiving circuit that receives and demodulates a modulated signal of a communication radio wave and outputs an electric field strength signal proportional to the electric field strength of the modulated signal. And a reference signal oscillator for calculating the line quality from the fluctuation of the phase difference between the output of the receiving circuit and the reference signal from the reference oscillator, and a demodulated signal of communication from the receiving circuit. In addition, when the line quality information from the line quality detecting means falls below a predetermined value, or when the electric field strength signal falls below a predetermined electric field strength value, a warning that outputs warning sound signal data It has a sound signal data output means and a warning sound output means for demodulating and converting the warning sound signal into an analog signal and outputting a warning sound.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the first invention.

In FIG. 1, the present embodiment includes a receiving circuit 1 which receives a modulated signal of a communication radio wave, frequency-converts it and outputs an intermediate frequency signal 1-1, and a reference oscillator 3 which outputs a reference signal 3-1. , The intermediate frequency signal 1-1 and the reference signal 3-1 are compared, and the line quality information 2-1 is obtained from the phase difference between these two signals.
, A demodulated signal receiving circuit 4 for receiving the demodulated voice signal and the channel quality information signal 2-1, an SP CODEC 5, and a receiver 6.

Next, the operation of this embodiment will be described.

The receiving circuit 1 receives the modulated signal of the communication radio wave, frequency-converts it, and outputs an intermediate frequency signal 1-1. The line quality detection circuit 2 compares the intermediate frequency signal 1-1 with the reference signal 3-1 output from the reference oscillator 3 to detect the line quality from the variation of the phase difference between the two signals, and the line quality information signal Output as 2-1. The demodulation signal receiving circuit 4 receives the line quality information signal 2-1, and when the value falls below a predetermined value, the SP CODEC 5 gives a warning instead of the decoded voice signal or by weighting the decoded voice signal. Send sound signal data. The SP CODEC 5 decodes the digital signal of the warning sound signal data output from the demodulation signal receiving circuit 4, converts it into an analog signal, and then outputs it to the receiver 6 as an audible signal.

FIG. 2 is a block diagram showing an embodiment of the second invention.

In FIG. 2, in the present embodiment, a receiving circuit 1 for receiving a modulated signal of a communication radio wave, frequency-converting and detecting it, and extracting an electric field strength signal (RSSI) 7-1, and an electric field strength signal (RSSI) 7 are shown. The demodulation signal receiving circuit 10 which receives -1 and outputs the warning sound signal data when the value is equal to or less than a predetermined value, the SP CODEC 5, and the receiver 6 are configured.

Next, the operation of this embodiment will be described.

The receiving circuit 7 receives the modulated signal, frequency-converts and detects it, extracts an electric field strength signal (RSSI) 7-1, and outputs the signal to the demodulation signal receiving circuit 10. The demodulation signal receiving circuit 10 uses an electric field strength signal (RSSI)
When 7-1 is received and the value falls below a predetermined value, warning sound signal data is output. SP CODEC5
Converts the warning sound signal data into an analog signal and then outputs it to the receiver 6 as an audible signal.

FIG. 3 is a block diagram showing an embodiment of the third invention. In FIG. 3, this embodiment shows a case in which the respective embodiments of the first and second inventions described above are combined. The same numbers are given to the same constituents as the example, and the receiving circuit 8
Has a function of combining the receiving circuit 1 and the receiving circuit 7, and the demodulation signal receiving circuit 11 has a function of combining the demodulation signal receiving circuit 4 and the demodulation signal receiving circuit 10.

Next, the operation of this embodiment will be described.

The demodulation signal receiving circuit 11 receives the field strength signal (RSSI) 8-1 from the receiving circuit 8 and the line quality detecting circuit 2.
When the line quality information signal 2-1 is received from the terminal and either of the respective values falls below the predetermined value,
It outputs warning sound signal data. The SP CODEC 5 decodes the digital signal of the warning sound signal data output from the demodulation signal receiving circuit 11, converts it into an analog signal, and then outputs it to the receiver 6 as an audible signal.

[0024]

As described above, according to the present invention, the line quality or the electric field strength is detected during use (during a call), and the deterioration of the wireless line quality is output as a warning sound based on the information. With this configuration, the user can directly listen to the state of deterioration of the wireless line quality during a call, and depending on the deterioration, the user can voluntarily hold or terminate the call and disconnect the line. Even if it becomes a (silent) state, there is no confusion, and it is possible to eliminate discomfort to the user.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the first invention.

FIG. 2 is a block diagram showing an embodiment of the second invention.

FIG. 3 is a block diagram showing an embodiment of the third invention.

FIG. 4 is a block diagram showing an example of a conventional digital communication type wireless telephone.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 receiving circuit 2 line quality detecting circuit 3 reference oscillator 4 demodulated signal receiving circuit 5 voice code decoder (SP CODEC) 6 receiver 7, 8, 9 receiving circuit 10, 11, 12 demodulated signal receiving circuit

Claims (3)

[Claims] 1. A reception circuit that receives and demodulates a modulated signal of a communication radio wave, and a reference signal oscillator that oscillates a reference signal, and a position of an output of the reception circuit and the reference signal from the reference oscillator. When the line quality detecting means for calculating the line quality from the fluctuation of the phase difference and the line quality information signal output from the line quality detecting means for receiving the demodulated signal of the communication from the receiving circuit are below a predetermined value. A wireless telephone comprising: a warning sound signal data output means for outputting warning sound signal data; and a warning sound output means for decoding and converting the warning sound signal data into an analog signal to output a warning sound. 2. A receiving circuit for receiving and demodulating a modulated signal of a communication radio wave and outputting an electric field strength signal proportional to the electric field strength of the modulated signal, and a communication demodulated signal from the receiving circuit. Warning sound signal data output means for outputting warning sound signal data when the electric field strength signal is lower than a predetermined electric field strength value, and outputting warning sound by decoding and converting the warning sound signal data into an analog signal. A wireless telephone having a warning sound output means. 3. A receiving circuit for receiving and demodulating a modulated signal of a communication radio wave and outputting an electric field strength signal proportional to the electric field strength of the modulated signal, and a reference signal oscillator for oscillating a reference signal, Line quality detecting means for calculating line quality from a variation in the phase difference between the output of the receiving circuit and the reference signal from the reference oscillator; and a line quality detecting means for receiving a demodulated signal of communication from the receiving circuit. A warning sound signal data output means for outputting warning sound signal data when the line quality information falls below a predetermined value, or when the electric field strength signal falls below a predetermined electric field strength value; A wireless telephone, comprising: a warning sound output means for demodulating and converting a warning sound signal into an analog signal to output a warning sound.