NETWORK SYNTHESIS APPLIED TO THE DESIGN OF TUNED OPTICAL FRONT-ENDS FOR MICROWAVE LIGHTWAVE SYSTEMS

An analysis of the tuned optical front-end noise performance of lightw ave receivers modulated by microwave carriers shows that under certain load conditions partial noise cancellation may be obtained. The Lette r presents a method of synthesising a tuning network between the photo diode and the receiver input stage which minimises noise over a select ed microwave bandwidth. The synthesis, carried out with lumped element s, makes no a priori assumptions on network topology, and an example i s given of the design of a 4 - 6GHz tuning network realised using an H EMT transistor.