KR930022747A

KR930022747A - Low noise down frequency converter

Info

Publication number: KR930022747A
Application number: KR1019920006988A
Authority: KR
Inventors: 강근모
Original assignee: 정장호; 금성정보통신 주식회사
Filing date: 1992-04-24
Publication date: 1993-11-24

Abstract

본 발명은 듀얼 게이트 전계 효과 트랜지스터(dual gate MESFET)를 사용하여 자체 국부 발진과 주파수의 혼합을 동시에 진행시켜 고주파를 영상 및 음성신호로 수신할 수 있는 중간 주파수로 변환시키도록 하는 저잡음 하향 주파수 변환기에 관한 것으로서, 밴드 패스필터 및 로우 패스필터 사이에 연결되어 자체 고주파 발진이 이루어지도록하고, 입력 고주파와 자체 발진 주파수의 혼합을 동시에 진행시키고, 불요파를 제거하여 안정된 중간주파수를 발생하는 자체 발진 막서회로를 구비하여 입력 고주파신호는 서로의 간섭 영향없이 자체 발진 및 혼합과정을 동시에 구현할 수 있을 뿐만 아니라 주파수 혼합과정에서 발생되는 고주파를 제거하여 안정된 중간주파수를 획득함은 물론 간단한 구성으로 인해 저잡음 하향 주파수 변환기의 소형화 제작에 기여할 수 있도록 한 것이다.The present invention uses a dual gate field effect transistor (dual gate MESFET) in a low-noise down-frequency converter to simultaneously convert the local oscillation and frequency mixing to convert the high frequency into an intermediate frequency that can be received as a video and audio signal The present invention relates to a self-oscillating oscillation circuit which is connected between a band pass filter and a low pass filter to achieve its own high frequency oscillation, and simultaneously mixes the input high frequency and the self oscillating frequency, and removes the unwanted wave to generate a stable intermediate frequency. With the furnace, the input high frequency signal can realize the self oscillation and mixing process simultaneously without affecting each other, and also obtain the stable intermediate frequency by eliminating the high frequency generated in the frequency mixing process, and also the low noise down frequency due to the simple configuration. Contributes to miniaturization of transducers It would be a help.

Description

Low noise down frequency converter

본 내용은 요부공개 건이므로 전문내용을 수록하지 않았음Since this is an open matter, no full text was included.

제1도는 종래의 저잡음 하향 주파수 변환기의 블럭도.1 is a block diagram of a conventional low noise downlink frequency converter.

제2도는 본 발명의 저잡음 하향 주파수 변환기의 블럭도.2 is a block diagram of a low noise downlink frequency converter of the present invention.

제3도는 본 발명에 다른 자체 발진 믹서회로.3 is a self-oscillating mixer circuit according to the present invention.

Claims

A first amplifier for three-stage low noise amplification of the input high frequency signal, a band pass filter for passing the output frequency only through a specific band, a low pass filter for passing the input intermediate frequency only through a specific band, and an intermediate frequency at a constant level A low noise down-frequency converter including a second amplifier for controlling gain, the low-pass frequency converter is connected between the band pass filter and the low pass filter so as to achieve its own high frequency oscillation, and simultaneously the mixing of the input high frequency and the self oscillation frequency And a low noise down frequency converter with a self-oscillating mixer circuit that generates a stable intermediate frequency by removing unwanted waves.

2. The self-oscillating mixer circuit according to claim 1, wherein the self-oscillating mixer circuit comprises a dielectric known oscillator which is a self-oscillating element of the first gate end of the field effect transistor, and an impedance match connected to the second gate end, the drain and the source end of the field effect transistor, respectively. First to third microstrip transmissions, first and second undesired noise cancelers connected to the first and second microstrip transmission lines to remove unnecessary frequencies, and connected to the field effect transistor drain terminal and mixed with frequency. A low noise town downlink frequency converter including a third unnecessary wave removing unit for removing a high frequency signal generated during the operation.

The self-oscillating mixer circuit according to claim 2, wherein the field effect transistor uses a dual gate gallium arsenide field effect transistor.

3. The self-oscillating mixer circuit according to claim 2, wherein the first to third unwanted wave removing units are? / 4 micro strip transmission lines.

※ Note: The disclosure is based on the initial application.