CN2267535Y

CN2267535Y - Microwave frequency modulation device for transferring or receiving video and audio signals

Info

Publication number: CN2267535Y
Application number: CN 95221503
Authority: CN
Inventors: 颜森辉
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-09-12
Filing date: 1995-09-12
Publication date: 1997-11-12
Anticipated expiration: 2005-09-12

Abstract

The utility model relates to a microwave frequency modulation device for transferring or receiving video and audio signals, which is mainly composed of a transferring circuit and a receiving circuit, wherein, the transferring circuit comprises a signal input end, an image processing circuit, a sound processing circuit, etc.; the receiving circuit comprises a receiving antenna, a low noise amplifier, a filter, etc. Transferred images and aural signals are tuned by the frequency modulation mode, and meanwhile, on the premise of not changing the quality of original images and sound signals, the transferring distance is increased, and the transferring frequency does not change under the influence of temperature so that the noise ratio of signals is increased; oscillation signals are generated by a phase-locked loop (PLL mode) to ensure the stability of generated signal frequency.

Description

The audio-visual transmission receiving system of microwave frequency modulation

The utility model relates to the audio-visual transmission receiving system of a kind of microwave frequency modulation.

At present, have the product that transmits reception video-audio signal function and be to use the 900MHZ frequency band, adopt the amplitude modulation tuning manner, its image quality is limited by the amplitude modulation tuning manner, is subject to disturb, and service range is short, and image quality is not good enough.Simultaneously tranmitting frequency can have drift significantly with temperature, and this frequency band is also very serious because of having a lot of radio communication product to make to interfere with each other.

The purpose of this utility model provides a kind of microwave mode of frequency regulation that adopts and transmits the device that receives video-audio signal, to address the above problem.

Another purpose of the present utility model is under the delivery quality prerequisite of the signal that guarantees image and voice, increases to transmit distance.

A purpose more of the present utility model is to make tranmitting frequency not be subjected to variations in temperature, and the noise that makes signal is than increasing.

Another purpose of the present utility model is that oscillator signal is to use phase-locked loop (PLL mode) to produce the stability of the signal frequency that is produced to guarantee.

The utility model is achieved in that and includes radiating circuit and receiving circuit, it is characterized in that: wherein radiating circuit is so to constitute: the picture intelligence by the input of picture intelligence input inserts the input that this signal is carried out the image processing circuit of pre-emphasis and amplification earlier, sound left and right sound track signals by the input of voice signal input also inserts the sound treatment circuit that its signal is carried out pre-emphasis earlier, and is tuned at paying on the carrier wave of 6MHZ and 6.5MHZ with mode of frequency regulation respectively.Insert behind the signal plus of above-mentioned image processing circuit and sound treatment circuit it is carried out the tuning vibration/tuner of frequency modulation, afterwards, order inserts the power amplifier that signal is amplified, first filter and the transmitting antenna of filtering harmonic wave again; Outwards emission receives for receiving circuit; Wherein receiving circuit is so to constitute; Its reception antenna links to each other with the input of low-noise amplifier, this low-noise amplifier output is connected to can be with the adjoining channel signal filtering, and the input of second filter of the compensation loss of signal that surface acoustic wave causes, the output of second filter is connected to the input that uses phase-locked loop (PLL mode) to produce the frequency mixer of local oscillated signal, it is a fixed bit standard that the output access of this frequency mixer can be adjusted input signal strength, can not make the signal that enters demodulator too strong and cause the input of the variable gain amplifier of distorted signals after the demodulation, the output of this variable gain amplifier then is connected to the input of the 3rd filter, the output of the 3rd filter then is connected to amplifier input terminal, the output of this amplifier is connected to the input of demodulator, the output of demodulator is connected to the input of image processing circuit and sound treatment circuit, image processing circuit and sound treatment circuit output are connected on the external circuit, be connected to the input of variable gain amplifier again with another output of demodulator, and oscillator output end is connected on another output of frequency mixer, to receive the signal of radiating circuit emission.

Main feature of the present utility model is to adopt mode of frequency regulation to transmit image and audio signal, and can make the transmission range lengthening, the noise that tranmitting frequency did not vary with temperature and made signal is than increasing, and wherein oscillator signal is to adopt the phase-locked loop to produce simultaneously, can guarantee the stability of the signal frequency that produces.

Fig. 1 is the utility model radiating circuit block diagram.

Fig. 2 is the utility model receiving circuit block diagram.

Fig. 3 is the electrical schematic diagram of the utility model radiating circuit.

Fig. 4 is the electrical schematic diagram of the utility model receiving circuit.

Fig. 5 is the electrical schematic diagram of the utility model receiving circuit.

Consult Fig. 1,2,3,4,5, the utility model is made of radiating circuit 10 and receiving circuit 20.This radiating circuit 10 is the inputs that are connected to image processing circuit 12 by picture intelligence input 11, be connected on the sound treatment circuit 14 with voice signal input 13, image processing circuit 12 and sound treatment circuit 14 outputs are connected to the input of vibration/tuner 15 respectively, be connected to the input of power amplifier 16 by vibration/tuner 15 outputs, be connected to the input of first filter 17 with the output of power amplifier 16, the output with first filter 17 is connected on the transmitting antenna 18 again.This receiving circuit 20 is the inputs that are connected to low-noise amplifier 22 by reception antenna 21, be connected to the input of second filter 23 by low-noise amplifier 22 outputs, be connected to the input of frequency mixer 24 with the output of second filter 23, be connected to the input of variable gain amplifier 25 with the output of frequency mixer 24, be connected to the input of the 3rd filter 26 again by variable gain amplifier 25 outputs, be connected to the input of amplifier 27 with the output of the 3rd filter 2, be connected to demodulator 28 inputs with amplifier 27 outputs, be connected to image processing circuit 29 and sound treatment circuit 201 inputs with demodulator 28 outputs, be connected on the external circuit with image processing circuit 29 and sound treatment circuit 201 outputs, be connected to the input of variable gain amplifier 25 again with demodulator 28 another outputs, and oscillator 202 outputs are connected to frequency mixer 24 another bring out on the end.

Picture intelligence by above-mentioned radiating circuit 10 input emissions carries out pre-emphasis and amplification through image processing circuit 12, and the left and right sound track signals of sound import is carried out pre-emphasis and is tuned at paying on the carrier wave of 6MHZ and 6.5MHZ with mode of frequency regulation respectively through sound treatment circuit 14 in addition.

The output of image processing circuit 12 and sound treatment circuit 14 is after addition before the vibration/tuner 15, it is tuning directly vibration/tuner to be carried out frequency modulation, by power amplifier 15 signal is amplified again, the harmonic wave that is produced is by the in addition filtering of first filter 17, by transmitting antenna 18 signal launched at last.

And the signal that picks up by reception antenna 21, amplify through low-noise amplifier 22, signal after the amplification passes through second filter 23 earlier with the illusion target signal filter, avoid the illusion signal to disturb, and then be connected to frequency mixer 24 and carry out mixing, then to fixed bit standard of output of variable gain amplifier 25, deliver on the demodulator 28 via the 3rd filter 26 and amplifier 27 again, the fundamental frequency signal that demodulator 28 is come out, through image processing circuit 29 and sound treatment circuit 201, image and audio signal separated being reduced into original signal output.

Frequency mixer 24 employed local oscillated signals are to use phase-locked loop (PLL mode), the stability of the signal frequency that is produced to guarantee.

Second filter, 26 purposes are with the adjoining channel signal filtering, and in order to compensate the loss that surface acoustic wave (SAW Filter) is caused.

The intensity that variable gain amplifier 25 can be adjusted input signal is a fixed bit standard, and can not make the signal that enters demodulator 28 cause distorted signals after the demodulation too by force.

Claims

1, the audio-visual transmission receiving system of a kind of microwave frequency modulation, include radiating circuit and receiving circuit, it is characterized in that: wherein radiating circuit is so to constitute: the picture intelligence by the input of picture intelligence input inserts the input that this signal is carried out the image processing circuit of pre-emphasis and amplification earlier, sound left and right sound track signals by the input of voice signal input also inserts the sound treatment circuit that its signal is carried out pre-emphasis earlier, and is tuned at paying on the carrier wave of 6MHZ and 6.5MHZ with mode of frequency regulation respectively; Insert behind the signal plus of image processing circuit and sound treatment circuit it is carried out the tuning vibration/tuner of frequency modulation, afterwards, order inserts the power amplifier that signal is amplified, first filter and the transmitting antenna of filtering harmonic wave again; Wherein receiving circuit is so to constitute: its reception antenna links to each other with the input of low-noise amplifier, this low-noise amplifier output is connected to can be with neighbour's frequency target signal filter, and the compensation surface acoustic wave causes the input of second filter of the loss of signal, the output of second filter is connected to the input that uses phase-locked loop (PLL mode) to produce the frequency mixer of local oscillated signal, it is a fixed bit standard that the output access of this frequency mixer can be adjusted input signal strength, can not make the signal that enters demodulator too strong and cause the input of the variable gain amplifier of distorted signals after the demodulation, the output of this variable gain amplifier then is connected to the output of the 3rd filter, the output of the 3rd filter is connected to amplifier input terminal, the output of this amplifier is connected to the input of demodulator, the output of demodulator is connected to the input of image processing circuit sound treatment circuit, image processing circuit and sound treatment circuit output are connected on the external circuit, be connected to the input of variable gain amplifier again with another output of demodulator, and oscillator output end is connected on another output of frequency mixer, to receive the signal of radiating circuit emission.