Power amplifier design. From mW to kW. Applications have included instrumentation, CDMA, TETRA, AM and digital airband (VDL) services, SSB and constant amplitude modulation schemes to several GHz. This has included the application of broadband technologies with multi-decade frequency respose and the development of physical designs using modern materials, devices and manufacturing techniques to produce highly competitive and reproducible products.
Transmitter linearisation technologies. Chris has been involved in complex feedback linearisation techniques (on-frequency feedback, IF feedback, and cartesian feedback), and predistortion.
Digital and analogue transmitter design. The implementation of transmitters in the digital domain, and particularly techniques for economically integrating linearisation technologies into medium bandwidth transmitters employing digital technology is of considerable interest. Areas of expertise in the analogue area include low-noise transmitter design.
Receiver Design. Particularly high linearity and low-noise receiver front-end design. Chris has had a substantial interest in this area for decades, and has an armoury of techniques at his disposal.
Frequency synthesiser design. Including mixed DDS/phase-lock synthesis, fractional-N synthesisers and oscillator design.
Antenna Design. Although not fundamentally an antenna engineer, Chris has considerable experience of antenna design, especially the design of efficient compact antennas integrated into equipment.
Digital design. Although Chris has experience of digital design, it is not a strong point and he does not offer it professionally. However, he has extensive contacts with digital hardware, software and DSP specialists, and can usually suggest links to experts within these fields.
Lecturing. Chris has lectured on post-graduate/CPD courses in RF Design at the University of Essex, for the Low Power Radio Association, Radio Frequency Investigation Limited and the Institute of Printed Circuits.
Other areas of interest have included Low Power Radio design, and industrial uses of RF technology and support to the scientific community.