A novel MICS chirp FSK receiver front-end

摘要

This paper presents a new receiver front-end for Chirp FSK MICS system dedicated to medical implantable devices. The receiver uses MICS band at 402-405 MHz. Chirped FSK pulses are used to encode the binary data. This enables non coherent FSK demodulator which simplifies the receiver architecture. The receiver is designed to communicate a maximum data rate of 100 Kbps. The various blocks parameters of the receiver are simulated and optimized to meet receiver specifications. The receiver realizes a sensitivity of -93 dBm, a voltage gain of 29 dB and a NF of 5.5 dB. Linearity is also evaluated and the receiver IIP3 is equal to -12.6 dBm. After the down conversion mixer, a variable bandwidth low pass filter, with 40-300 MHz control range, passes the desired channel signal while eliminating in-band interference and thus lowering the sensitivity of the receiver.