A Digital Filtering ADC With Programmable Blocker Cancellation for Wireless Receivers

• Published in: IEEE journal of solid-state circuits Vol. 53; no. 3; pp. 681 - 691
• Main Authors: Qiwei Wang, Shibata, Hajime, Liscidini, Antonio, Carusone, Anthony Chan
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.03.2018; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Analog to digital converter (ADC); Analog to digital converters; Attenuation; Baseband; blocker; Cancellation; Detection algorithms; digital; digital to analog converter (DAC); Digital to analog converters; filtering; Filtration; Gain; long-term evolution (LTE); Mobile communication systems; Noise levels; reconfigurable; Transfer functions; Wireless communication; Wireless communications; wireless receiver (RX); Wireless sensor networks
• ISSN: 0018-9200; 1558-173X
• DOI: 10.1109/JSSC.2017.2766213

This paper presents a long-term evolution (LTE) receiver (RX) front end with a digital filtering analog to digital converter (ADC) in the baseband to perform multi-band blocker cancellation. The digital filtering ADC has a digitally defined transfer function that is highly reconfigurable and insensitive to PVT variations. The dynamic range requirement of the blocker cancellation feedback digital to analog converter (DAC) is relaxed with a trivial uncalibrated first-order passive high-pass filter. The programmable digital filter provides 34.9-dB attenuation of transmitter leakage and variable attenuation of an additional blocker anywhere in the frequency range 17.5-107.5 MHz. A blocker detection algorithm for this RX is presented and takes approximately 26 μs to converge. The RX front end operates at 1.8 GHz with a noise figure of 3.9 dB and IIP3 of -5 dBm, and consumes only 20.4-37.5 mW, the lowest among the state-of-the-art designs.