Open AccessDesign of a ±0.15 dB accurate baseband detector for FMCW radars employing inherent PVT cancellation
Author(s) -
ElShennawy Mohammed,
Joram Niko,
Ellinger Frank
Publication year - 2017
Publication title -
iet circuits, devices and systems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.251
H-Index - 49
eISSN - 1751-8598
pISSN - 1751-858X
DOI - 10.1049/iet-cds.2015.0352
Subject(s) - baseband , detector , electronic engineering , automatic gain control , compensation (psychology) , transceiver , chip , computer science , sensitivity (control systems) , engineering , electrical engineering , amplifier , cmos , psychology , psychoanalysis
This study presents design methodologies for high accuracy baseband detectors for use in automatic gain control (AGC) loops. These loops are used in many applications to stabilise the signal level in a transceiver chain. In a wireless frequency modulated continuous wave (FMCW) radar receiver for example, it is desired to maintain a constant baseband signal level at the receiver output prior to the analogue‐to‐digital converter. Due to the AGC loop feedback action, the accuracy of this output level directly depends on the detector accuracy. In this study, a detector design employing inherent cancellation of process, voltage and temperature (PVT) variations without the need for any complex compensation schemes is proposed. Measurement results of a fabricated test chip are in good agreement with simulations achieving ±0.15 dB accuracy over temperature, supply and part‐to‐part variations. The fabricated detector prototype on an IBM 0.18 µm technology has an active area of 0.05 mm 2 and draws 1 mA from a 3 V supply. An integrated AGC loop including the proposed detector achieves a 52 dB dynamic range consuming an overall 9 mW power. To the best of the authors’ knowledge, the proposed detector has the highest uncalibrated accuracy reported up to date.