Design and Implementation of a Low Noise Block for Extended C-Band Earth Station

In this paper, we design and implement a compact low noise block (LNB) for extended C-band Earth Station in satellite communication systems which converts the radio frequency (RF) signal from extended C-band (3.4 – 3.625 GHz) to a fixed 70 MHz intermediate frequency (IF) signal. The LNB consists of a three-stage low noise amplifier, a band pass filter, a frequency mixer, a local oscillator, IF amplifiers and IF filters. It is fabricated by Rogers RO4350B substrate (εr = 3.48, hsub = 0.762mm, tan δ = 0.0035). With power supply of +12V and 300mA, the LNB yields overall conversion gain of 80 dB, noise figure of less than 1.1 dB, and output power at 1 dB compression of +18dBm. The power sensitivity of the LNB is lower than -80dBm. Simulated and measured results are described to show the performances of the proposed LNB