Title :
An ultra-broadband compact mm-wave butler matrix in CMOS for array-based MIMO systems
Author :
Jong Seok Park ; Taiyun Chi ; Hua Wang
Author_Institution :
Sch. of Electr. & Comput. Eng., Georgia Inst. of Technol., Atlanta, GA, USA
Abstract :
This paper presents the design scheme of an ultra-broadband compact mm-wave Butler Matrix. The design employs new transformer-based swapped-port couplers and lumped LC-based π-network phase shifters to achieve an extremely compact chip size and ultra-broad bandwidth. This scheme is implemented as a 4×4 Butler Matrix in a standard 65nm CMOS technology with a core area of 0.335×0.215 mm2 and a broad bandwidth of 9.8 GHz with the center frequency of 63 GHz. This Butler Matrix design also achieves small insertion loss of 2.77 dB and high-quality matching among the ports with less than 0.6 dB amplitude mismatch and less than 5° phase imbalance at 63 GHz. Based on the measured S-parameters, the four concurrent electrical array patterns of the Butler Matrix achieve its array peak-to-null ratio of better than 17dB between 57 GHz and 67 GHz.
Keywords :
CMOS integrated circuits; MIMO communication; S-parameters; antenna arrays; millimetre wave phase shifters; CMOS technology; S-parameters; array peak-to-null ratio; array-based MIMO systems; bandwidth 9.8 GHz; concurrent electrical array patterns; extremely compact chip size; frequency 57 GHz to 67 GHz; high-quality matching; loss 2.77 dB; lumped LC-based π-network phase shifters; phase imbalance; size 65 nm; transformer-based swapped-port couplers; ultra-broad bandwidth; ultra-broadband compact mm-wave butler matrix; Antenna measurements; Butler matrices; CMOS integrated circuits; Couplers; Frequency measurement; Phase measurement; Ports (Computers); Butler Matrix; CMOS integrated circuits; MIMO; beam-forming; phased-array; transformer-based swapped-port quadrature coupler;
Conference_Titel :
Custom Integrated Circuits Conference (CICC), 2013 IEEE
Conference_Location :
San Jose, CA
DOI :
10.1109/CICC.2013.6658548