TY - JOUR
T1 - A Beamformer with constant-gm vector modulators and its spatial intermodulation distortion
AU - Soer, M.C.M.
AU - Klumperink, Eric A.M.
AU - van den Broek, Dirk-Jan
AU - Nauta, Bram
AU - van Vliet, Frank E.
PY - 2017/3/1
Y1 - 2017/3/1
N2 - Spatial interference rejection in analog adaptive beamforming receivers can improve the distortion
performance of the circuits following the beamforming network, but is susceptible to the non-linearity of
the beamforming network itself. This paper presents an analysis of intermodulation product cancellation
in analog active phased array receivers and verifies the distortion improvement in a 4-element adaptive
beamforming receiver for low power applications in the 1.0 to 2.5 GHz frequency band. In this architecture, a constant-Gm vector modulator is proposed which produces an accurate equidistance square constellation, leading to a sliced frontend design that is duplicated for each antenna element. By moving the transconductances to RF, a four-fold reduction in power is achieved, while simultaneously providing input impedance matching. The 65-nm implementation consumes between 6.5 and 9 mW per antenna element, and shows a +1 to +20 dBm in-band, out-of-beam IIP3 due to intermodulation distortion reduction.
AB - Spatial interference rejection in analog adaptive beamforming receivers can improve the distortion
performance of the circuits following the beamforming network, but is susceptible to the non-linearity of
the beamforming network itself. This paper presents an analysis of intermodulation product cancellation
in analog active phased array receivers and verifies the distortion improvement in a 4-element adaptive
beamforming receiver for low power applications in the 1.0 to 2.5 GHz frequency band. In this architecture, a constant-Gm vector modulator is proposed which produces an accurate equidistance square constellation, leading to a sliced frontend design that is duplicated for each antenna element. By moving the transconductances to RF, a four-fold reduction in power is achieved, while simultaneously providing input impedance matching. The 65-nm implementation consumes between 6.5 and 9 mW per antenna element, and shows a +1 to +20 dBm in-band, out-of-beam IIP3 due to intermodulation distortion reduction.
KW - EWI-26902
U2 - 10.1109/JSSC.2016.2639545
DO - 10.1109/JSSC.2016.2639545
M3 - Article
VL - 52
SP - 735
EP - 746
JO - IEEE journal of solid-state circuits
JF - IEEE journal of solid-state circuits
SN - 0018-9200
IS - 3
ER -