Research Of Multi-channel Processing Receiver Chip Based On CMOS Technology

With the rapid development of wireless communication technology,wireless receivers are playing an important role in military fields such as radar imaging and early warning aircraft,and civilian fields such as intelligent terminals and the Internet of Things.Ultra-wideband communication technology has become a hot research direction with its significant advantages such as high transmission rate,low power consumption,and high bandwidth,and has important application prospects.Based on the above practical significance and social needs,this paper designs and implements an ultra-wideband RF receiver chip working at 0.2?9GHz based on 55 nm CMOS process.The chip adopts multi-channel processing architecture and partial channel multiplexing function,which can realize the demodulation of received signals under ultra-wide RF bandwidth.The specific research contents of the chip are as follows:1: Based on the multi-channel receiving technology,an 8-channel receiving system is designed.The channel adopts a multi-mode demodulation scheme according to the demand,and uses the radio frequency switch model of the process to select the time decomposition and modulation scheme.In saturated working conditions,4 channels can be used to achieve 8 channels of time-sharing demodulation.This architecture effectively reduces the frequency of mixing,optimizes the number of mixers in the multi-path,and significantly improves the signal leakage between paths.The combination of multiple down-conversion and low-pass filters avoids band-pass filters.The use of,reduces the power consumption of the system while improving the integration of the system,greatly reducing the chip area.2: Aiming at the difficulty of achieving ultra-wideband operating range of low-noise amplifiers,a wideband low-noise transconductance amplifier(LNTA)based on the gm-enhanced current mirror topology multi-stage structure is studied.This structure inserts the broadband voltage before the traditional single-stage LNTA to increase its transconductance,while using active feedback to improve bandwidth and linearity.The low-noise transconductance amplifier converts the RF input voltage signal into a current signal output in the 0.2?9GHz broadband frequency range,and drives the next-stage passive mixer.3: Aiming at the realization of working channel switching,a dual-mode mixer with switchable working mode is studied.It adopts a passive switch mixing structure and can choose two working states of direct and mixing.Aiming at the odd-order harmonic interference problem of the mixer,a mixer with harmonic suppression function is designed.On the basis of the traditional active Gilbert mixing structure,a specific ratio of transconductance gain is used to cancel the third and fifth Subharmonics.In order to generate the local oscillator signal required for mixing in the system,a frequency divider is designed,and a two-frequency divider,a four-frequency divider and an eight-frequency divider are designed with the D latch based on the CML structure as the basic unit.4: Aiming at the problem of excessively large differential LC filter area,an elliptical LC low-pass filter with passband widths of 4.2GHz and 1.8GHz was designed,and the inductive coupling structure was used to improve its integration.At the same time,the Gm-C filter structure is used to design active low-pass filters with passband widths of 0.6GHz and 0.2GHz,which can achieve the function of signal amplification while realizing the filtering function.