A Beamformer with constant-gm vector modulators and its spatial intermodulation distortion

M.C.M. Soer, Eric A.M. Klumperink, Dirk-Jan van den Broek, Bram Nauta, Frank E. van Vliet

  • 2 Citations

Abstract

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.
Original languageEnglish
Pages (from-to)735-746
Number of pages12
JournalIEEE journal of solid-state circuits
Volume52
Issue number3
DOIs
StatePublished - 4 Jan 2017

Fingerprint

Beamforming
Intermodulation distortion
Modulators
Antennas
Intermodulation
Transconductance
Frequency bands

Keywords

  • EWI-26902

Cite this

Soer, M.C.M.; Klumperink, Eric A.M.; van den Broek, Dirk-Jan; Nauta, Bram ; van Vliet, Frank E. / A Beamformer with constant-gm vector modulators and its spatial intermodulation distortion.

In: IEEE journal of solid-state circuits, Vol. 52, No. 3, 04.01.2017, p. 735-746.

Research output: Scientific - peer-reviewArticle

@article{d5cb9c75bbd643d9a169d5d75256b8dc,
title = "A Beamformer with constant-gm vector modulators and its spatial intermodulation distortion",
abstract = "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.",
keywords = "EWI-26902",
author = "M.C.M. Soer and Klumperink, {Eric A.M.} and {van den Broek}, Dirk-Jan and Bram Nauta and {van Vliet}, {Frank E.}",
year = "2017",
month = "1",
doi = "10.1109/JSSC.2016.2639545",
volume = "52",
pages = "735--746",
journal = "IEEE journal of solid-state circuits",
issn = "0018-9200",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
number = "3",

}

A Beamformer with constant-gm vector modulators and its spatial intermodulation distortion. / Soer, M.C.M.; Klumperink, Eric A.M.; van den Broek, Dirk-Jan; Nauta, Bram ; van Vliet, Frank E.

In: IEEE journal of solid-state circuits, Vol. 52, No. 3, 04.01.2017, p. 735-746.

Research output: Scientific - peer-reviewArticle

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 - 2017/1/4

Y1 - 2017/1/4

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

T2 - IEEE journal of solid-state circuits

JF - IEEE journal of solid-state circuits

SN - 0018-9200

IS - 3

ER -