Ossi Pollanen

Comparison of measured and simulated /spl pi//4-DQPSK adjacent channel power using a functional high power amplifier model

A novel functional nonlinear high power amplifier model for radio communication system simulations is used to study spectrum regeneration of a nonlinearly amplified /spl pi//4-DQPSK signal. Simulated adjacent channel power has been compared to measured results, and a very good resemblance is found. This together with a satisfactory intermodulation behaviour in a two-tone test simulation verifies that the proposed model is applicable to accurate adjacent channel power prediction in radio system simulations.

Integrated power measurement circuit for RF power amplifiers

A RF power measurement circuit, which operates on the same chip with an integrated RF power amplifier, is presented. The circuit is capable of measuring load variation dependent output power changes. Full integration saves the PCB area needed for the line coupler used in conventional power detection methods. The circuit was realised using GaAs MMIC technology and tested on a standard FR4 test board at 900 MHz. The circuit detects RF power in a range of 35 dB with a sensitivity of 0.8 V/W showing good agreement with the simulations.