JPS6053326A - Transmitter provided with modulation signal delay circuit - Google Patents

Abstract

PURPOSE:To attain communication without interruption of head or tail of speech by retarding a time of a modulation input of a transmtter reaching a modulator by a time corresponding to the leading time of the transmitter. CONSTITUTION:A delay circuit D is inserted between a low frequency amplifier AFAMP and a modulator MOD to retard a modulation signal and a timer circuit TIM to hold the transmission function by a delay time of the modulation signal at the end of call is connected to a voice control VOK. Since a switching circuit is kept in contact state with the timer circuit TIM by a prescribed time from the time when a modulation signal fa not subject to any delay is lost at the end of call, the transmitter is brought into the operating state during that time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmitter that prevents disconnection at the beginning of a conversation in a breath daughter type or voice control type communication device.

A transmitter of a communication device that employs the breathtalk system, such as a transmitter of a mobile radio communication device, is generally shown as a circuit as shown in FIG. That is, the modulation signal fa is a low frequency amplifier (AF'AMP)
is input to the modulator MOD via the oscillator O8C, which modulates the output of the oscillator O8C. The high frequency amplifier R.FAMP amplifies the power of the modulated signal and supplies it to the antenna ANT, but since it is necessary to alternately switch between transmission and reception, the transmission function is cut off during reception. At this time, in order to save current consumption and prevent the generation of unnecessary noise, the power supply to all or part of the circuits of the transmitter block is turned off, and only when transmitting, turn on the power supply by using a press switch FT-8 attached to the microphone, etc. Usually, the transmitter is fully operated.

However, due to the transient phenomenon that exists in each block of the transmitter, it generally takes 30 to 500+n5ec for 9 hours before the radio wave energy is properly radiated from the antenna ANT, so the transmitter starts up immediately after the power is turned on. This has the drawback of causing a phenomenon in which the modulated information added up to that point is interrupted, so-called speech cutting.

Fig. 2 is a block diagram showing a voice control system transmission l1M@, in which the press function of the transmitter is automatically performed by detecting the presence of human input fa modulating voice signals, etc. The degree of the above-mentioned speech cutting was even greater than that of the Breathtalk transmitter.

In order to deal with this disconnection at the beginning of a story, conventional solutions include shortening the transition time of each block of the transmitter, or sacrificing all power consumption to constantly supply power to blocks that take a long time to start up. Other than taking measures, li! was released a little while after the press. The only measures taken were operational measures such as offering monetary incentives for the first episode.

However, there is a limit to the reduction in the rise time of each block of the transmitter, and there are considerable operational inconveniences, and neither of these is a fundamental solution.

The present invention has been made to eliminate the drawbacks of conventional communication devices as described above, and is applicable to mobile radio transmitters that operate the transmitter only when transmitting, such as the breath talk method or the voice control method. It is an object of the present invention to provide a transmitter equipped with a modulation signal delay circuit that delays the time when the G-key input of the transmitter reaches the F-key by a time corresponding to the rise time of the transmitter.

The present invention will be described in detail below based on embodiments shown in the drawings.

FIG. 3 is a block diagram showing an embodiment of a transmitter according to the present invention. In this figure, a delay circuit Di is inserted between the low frequency amplifier AFAMP and the modulator MOD in order to delay the modulated signal, and furthermore, in order to maintain the transmission function for the delay time of the 9th tone signal at the end of the call. Connect to the timer circuit TIM-6 voice control v or <.

Since the present invention is constructed as described above, the modulation signal fa is input to the modulators M and OD through the low frequency amplifier AFAMP6 and after being delayed by a predetermined time by the delay circuit. At this time, the oscillator OSC, the modulator MOD, and the high frequency amplifier R・F'
The power to the AMP is turned off and it is in a non-operating state, and the modulation signal fa, which is the microphone output (not shown), is output from the voice control V.
When OK is received, the aforementioned oscillator OSC, modulator MOD, and high frequency amplifier R/FAMPK are powered on via the switching circuit in the voice control VOK, and the transmission block is activated.

In addition, at the end of the call, the switching circuit in 1 voice control
The transmitter is kept active by the IM during this time. Since the transmitter continues to send out the carrier wave until the modulated signal MODin delayed by the delay circuit reaches the modulator lVt0D, the end of the signal is not cut off.

FIG. 4 is a time chart showing the operating state of each block in FIG. 3.

The modulated signal fa is delayed by a time 'r by a delay circuit and input to the modulator MOD. In addition, the power supply Vo for the oscillator OSC, modulator MOD, and high frequency amplifiers H and F A MP is
ut is delayed by the rise time t1 of the voice control VOK, and the high frequency output RF nu t is delayed by the rise time t2 of each block of the transmitter, and the antenna A is delayed by the rise time t1 of the voice control VOK.
Since the radiation is emitted from the NT, the delay time T of the delay circuit J) is set to correspond to t, and the timer '
The time held by VIM may be slightly longer than T.

In the above embodiment, only the case where the entire operation of the transmitter is controlled by the power supply Vout to the transmitter has been explained, but the present invention does not need to be limited to this, and for example, the oscillation output of the oscillator O8C can be connected to the next stage circuit. It is clear that this can also be applied to the case where the transmission output is controlled depending on whether it is turned on or off.

Further, the positions of the delay circuit 1) and the timer circuit TIM are not limited to the above-described embodiments, and for example, the delay circuit 1) may be inserted at the front stage of the low frequency amplifier AFAMP,
'IM may not be involved in the voice control VOK, but may directly control the entire power supply circuit for the transmitter, which is provided separately.

Further, the present invention can be easily implemented by using a bucket brigade device (BBD) 2 as a component of the delay circuit.

Since the present invention operates as 4M as explained above, the modulation signal fa reaches the transformer FJ modifier MOD only after the rise time of the transmitter has elapsed, and thereafter modulates the carrier wave sequentially with a delay time t. Therefore, the speaker is i
Since it is possible to communicate without being forced to perform special operations and without cutting off the beginning or end of a sentence, it has a remarkable effect on clear communication.

[Brief explanation of drawings]

Figure 1 is a block diagram of a conventional Breathtalk transmitter.
FIG. 2 is a block diagram of a conventional voice control transmitter, FIG. 3 is a block diagram of an embodiment of the present invention, and FIG. 4 is a time chart 1 showing the operation of each block in FIG. 1゜AFAMP・・・・・・・・・Low frequency amplifier. It, FAM, P...-High frequency amplifier. MOD...Variable 1 bar, VOK...Voice control block, fa'''--Modulation signal, L)...Delay circuit, Vcc...
···power supply. MODin...Modulator input signal patent applicant Toyo Tsushinki Co., Ltd.

Claims (3)

[Claims] (1) In a breath-talk type transmitter or a voice-controlled type transmitter that activates the transmitter by the presence of a modulated signal, the modulated signal is applied to the modulator of the transmitter for a time corresponding to the rising edge of the transmitter. A transmitter equipped with a modulated signal delay circuit characterized by delaying the modulation signal. (2) A bucket brigade device is used as the delay circuit.
A transmitter equipped with a modulated signal delay circuit according to claim 11, characterized in that the transmitter uses the modulated signal delay circuit according to claim 11. (3) A transmitter equipped with a modulated signal delay circuit according to claim 11 or (2), characterized in that the transmitter is equipped with a timer that maintains the operation of the transmitter for the delay time of the modulated signal at the end of a call. .