Decade Tuning Wide IF Instrumentation Receiver

This paper describes the development of the receive section of an instrumentation transceiver. The radio is designed for high linearity, gain and phase flatness, and is capable of tuning from 0.4-4GHz in 1Hz steps with an IF bandwidth of 20MHz. Its performance is intended to be capable of testing 2G, 3G, LTE, and WIMAX systems. A high first IF avoids multiple switched filters while maintaining good spurious performance. The design uses SMT packaged MMIC amplifiers and mixers, microstrip, coaxial resonator, and lumped element filter technologies and a high performance synthesiser architecture based around off-the-shelf VCOs. A 16 bit 130MHz ADC takes the signal into the digital domain for final down conversion to complex base-band. Two high performance FPGAs and a high speed serial link to further processing are available for implementation of digital equalisation, calibration offsets, filtering, and software defined demodulators.

Daniel Cletheroe received his MEng in electronic engineering with music technology systems from the University of York in 2002. After sponsorship as a student he joined the radio group at Plextek Ltd. He is involved in analogue and radio frequency circuit level design on projects including a low-cost high-volume VHF transceiver, GPS, and test equipment.