Frequency conversion assemblies of KeyLink Microwave

In a communication system, the mixer (frequency converter) plays a key role. The mixing circuit includes three components: local oscillator, nonlineardevice and band-pass filter. The purpose of mixing is to ensure that the receiver obtains higher sensitivity, sufficient amplification and appropriatepassband, and can work stably at the same time. Therefore, there are some requirements for the performance of the mixer:

1. Frequency stability, especially for up-converter, must ensure the emission carrier frequency index requirements. Taking INTELSAT as an example, the specified frequency tolerance of various transmitting carriers is shown in Table 1. In order to meet the requirements in Table 1, the local oscillators in the upconverter all use crystal oscillators withhigh stability. First, second, local oscillator adopts frequency synthesis phase lock technology.

2. Easy to change operating frequency. In the international satellite communication system, the satellite circuit business is increasing at a speed of about 15% every year. Inorder to meet the needs of circuit development, the frequency of the whole system is planned to be fully adjusted once every two years, local frequency changes are morefrequent. Therefore, the frequency of receiving and sending of the earth station may also change frequently. In order to meet the needs of this change, it is required that thefrequency of up and down converter can be adjusted, and the step level is generally 1.25MHz, 250Hz, etc.

3. With the rapid development of digital communication, the requirements for the phase characteristics of up-down converter are higher, especially for the phase noise offrequency synthesizer. typical value of phase noise:

100Hz－60dBc/Hz

1kHz－70 dBc/Hz

10kHz－75 dBc/Hz

100kHz－85 dBc/Hz

Keylink frequency conversion components can bring stable frequency conversion output to the system. We also provide RF amplifier and related services. If you are interested in our products, please contact info@keylinkmw.com or 0086-18109037151 (Cel/Whatsapp).