By Topic

A comparison of wide bandwidth quadrature demodulators using computer modelling

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $31
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

1 Author(s)
Owen, J.D. ; EnTegra Ltd., UK

In radar systems that need to measure target range and velocity accurately the transmitter and receiver chains use the same local oscillators. This ensures that the phase of the target return only contains the targets range information. The radar receiver demodulates the signal into inphase (I) and quadrature (Q) signals, using a quadrature demodulator. A conventional analogue quadrature demodulator is shown. The nature of demodulating one signal into two signal paths means that any imbalance in the characteristics of the paths causes an error (called the image) in the IQ samples. The image can appear as a target which does not exist and is therefore undesirable. Traditionally the demodulation has been performed using analogue components, then converting to digital once the signals are at baseband. With advances in ADC and DSP technology, digital methods are becoming possible at radar bandwidths. These techniques have been widely documented over the last few years. What has not been documented to our knowledge is a comparison of wide bandwidth quadrature demodulator techniques. That was the objective of a study by Racal Radar Defence Systems

Published in:

Radar 97 (Conf. Publ. No. 449)

Date of Conference:

14-16 Oct 1997