Dual-Band Direct Conversion Receiver With Additive Mixing Architecture

Seong-Mo Moon,Han Lim Lee

doi:10.1109/access.2022.3149346

Abstract

A dual-band direct conversion receiver based on additive mixing architecture for low-cost and multi-mode wireless communication systems is proposed. The proposed receiver consists of two active four-port junctions for additive mixing and one-stage dual-band polyphase filter for quadrature LO signal generation. Each four-port junction is fabricated with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.18~\mu \text{m}$ </tex-math></inline-formula> CMOS technology and configured by an active balun, two buffer amplifiers, two active combiners and two power detectors. The proposed polyphase filter is implemented using type-I architecture adopting one-stage and R-LC resonance type for low power and dual-band operation. The phase and amplitude calibration schemes are also integrated to effectively correct I/Q mismatch within the proposed architecture. The calibration ranges for the phase and amplitude mismatches show 8° and 14 dB, respectively. The validity of the proposed receiver based on additive mixing method is successfully demonstrated by demodulating 16-QAM signals with 40 Mbps at the dual band of 900 MHz and 2.4 GHz.

Highlights

Modern wireless communication systems typically use direct conversion receivers (DCR) for high-speed multi-band or multi-mode applications to effectively demodulate various modulated signals like M-ary quadrature amplitude modulation (M-QAM)
Some DCRs based on the six-port techniques were proposed for software defined radio (SDR) front-ends [4,5,6]
To achieve the dual-band performance with low circuit complexity, low power and compact size, a dual-band polyphase filter (PPF) and I/Q mismatch calibration scheme are adopted in the proposed architecture

Summary

INTRODUCTION

Modern wireless communication systems typically use direct conversion receivers (DCR) for high-speed multi-band or multi-mode applications to effectively demodulate various modulated signals like M-ary quadrature amplitude modulation (M-QAM). The six-port network has been typically implemented by microwave passive circuits such as hybrid coupler or Wilkinson power divider as shown in Fig. 1 (b). The hybrid coupler with standard varactor diodes has been conventionally used to implement dual-band or multi-band operations [9] Another typically used technique in the six-port is to utilize the wideband power dividers or combiners and the polyphase LO network [10] as shown in Fig. 1 (c). The previously reported active four-port junction has shown the compactness compared to the conventional passive network, the operation flexibility like multi-band operation has not been demonstrated yet. In this paper, a new six-port DCR architecture with a dual-band operation is proposed to further extend the effective use of the active six-port technique. To achieve the dual-band performance with low circuit complexity, low power and compact size, a dual-band polyphase filter (PPF) and I/Q mismatch calibration scheme are adopted in the proposed architecture

DESIGN AND ANAYSIS OF THE PROPOSED DUAL-BAND SIX-PORT DCR

ARF ALO cos 2

FABRICATION AND MEASUREMENT

CONCLUSION