High-linearity low-noise short wave broadband receiver

Abstract

The invention discloses a high-linearity low-noise short wave broadband receiver which comprises a radio frequency input filter circuit, a radio frequency switch frequency-selecting assembly, a mode selecting circuit, an LC low-pass filter, a crystal oscillator amplifying circuit, a frequency synthesizer circuit, a frequency synthesizer driving circuit, a frequency mixer, a multistage crystal filter circuit and a multistage amplifying circuit. The radio frequency input filter circuit, the radio frequency switch frequency-selecting assembly and the mode selecting circuit are sequentially cascaded, an output of the mode selecting circuit is connected with the LC low-pass filter and then connected to the radio frequency input end of the frequency mixer. The crystal oscillator amplifying circuit, the frequency synthesizer circuit and the frequency synthesizer driving circuit are sequentially cascaded, and an output of the frequency synthesizer driving circuit is connected to the local oscillator input end of the frequency mixer. The intermediate frequency output of the frequency mixer is connected with the multistage amplifying circuit. The high-linearity low-noise short wave broadband receiver is high in scanning speed, high in linearity, low in noise and high in intermediate frequency and image frequency inhibition degree. An intermediate frequency output band is free of interference signal. The high-linearity low-noise short wave broadband receiver is suitable for broadband application and is low in power consumption.

Description

technical field [0001] The invention relates to a short-wave receiver, in particular to a novel high-linearity and low-noise short-wave wideband receiver used in the field of short-wave communication. Background technique [0002] Since it was discovered in 1921 that short-wave can realize long-distance communication, short-wave communication has developed rapidly and has become an important means of medium and long-distance communication in all countries in the world. It is widely used in military, political, diplomatic, commercial and other fields or departments and plays an important role. . Shortwave communication can transmit various forms of information including telegraph, telephone, voice broadcast and so on. [0003] Short-wave communication has many significant advantages: it can realize long-distance communication without building a relay station, the short-wave antenna construction period is short, and the construction and maintenance costs are low; the equipmen...

AI Technical Summary

Problems solved by technology

At the same time, short-wave communication also has some obvious shortcomings: narrow frequency band; small communication capacity; sky-wave channel is a variable parameter channel, and the signal transmission stability is poor; atmospheric and industrial radio noise interference is serious

With the rapid development of broadband, hopping, and spread spectrum communication technologies in short-wave communication, the traditional, single narrow-band reception can no longer meet the requirements. Broadband reception must be introduced in short-wave communication, and the stability and anti-interference ability of the receiver are also important. needs to be further improved

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