Reconfigurable GNSS RF Receiver for High-Precision Positioning and Orientation

Aiming at the problem of multiple types of requirements and large volume, this paper introduced a highly integrated and reconfigurable Global Navigation Satellite System (GNSS) Radio Frequency (RF) receiver for high-precision positioning and orientation of satellite navigation. By adopting four reconfigurable reception channels and receiving full frequency band GNSS signals in parallel, it achieved a single chip supporting high-precision positioning or orientation applications, significantly reducing the volume and cost of navigation terminals. To improve broadband signal reception, the paper proposed a new type of inductorless high linear low noise transconductance amplifier (LNTA). It can eliminate the use of source and load inductors, reduce gain and noise fluctuations when operating in navigation signals at different frequency points, and it is conducive to the reconfiguration of multimode and multi frequency reception and reduces the power consumption of LNTA. A novel IQ phase compensation method was proposed to address the issue of IQ phase imbalance. A programmable switch array with variable impedance was directly designed on the clock controlled latch path of the binary frequency division circuit. By changing the delay time of the 25% duty cycle orthogonal LO, the corresponding branch output LO phase adjustment was realized, achieving calibration of IQ imbalance and improving the image rejection rate (IRR). Testing data shows that the RF receiver achieves full band signal coverage of GNSS from 1.15 to 1.65 GHz, a minimum noise figure of 2.7 dB, and an output third-order intermodulation point power of 34.7 dBm. Adopting a low intermediate frequency and zero intermediate frequency reconfigurable architecture, it can flexibly receive multimode GNSS signals with a bandwidth of 0.8~80 MHz. By compensating for IQ imbalance and improving channel layout, 58.1 dB IRR and 57 dB channel isolation can be achieved, effectively reducing the impact of image interference and inter channel interference. Under a 1.2 V power supply, the power consumption of the receiving channel is only 24.7 mW, which can meet the high integration and diversified application requirements of high-precision positioning and orientation GNSS RF receivers.