A circuit is disclosed for a receiver front-end for a Personal Handy Phone. The circuit consists of a high frequency mixer consisting of a cascade downmixer, tapped at the center, and followed by a common source intermediate (IF) amplifier. The combination of downmixer and IF amplifier provides a high third order intermodulation suppression and a robust conversion gain. The proposed circuit can also be applied to other FET technologies and other uses.

A highly efficient radio frequency (RF) transmitter provides both wide bandwidth and an extended power control range. The RF transmitter includes stage switching, bias adjustment, and drain supply modulation. These components are used to provide fine and coarse power control and EER envelope fluctuations. The RF transmitter is useful in wireless communications to increase both handset talk time and battery life.

A method and apparatus for predicting signal values for signals that have not yet been received wherein the information stream transmitted has been divided into a first stream and a second stream. A first Q component is predicted based on values stored in a state memory for the first bit stream. A first I component is predicted using the first predicted Q component and a previous bit from the state memory for the first bit stream. Then, a second Q component is predicted based on values in the state memory for the second bit stream. A second I component is then predicted using the second predicting Q component and the previous bit from the second bit stream. The first I component and the second Q component are added to obtain a combined I value and the first Q component and the second I component are added to obtain a combined Q value. Finally, the combined I value, the combined Q value, and a channel coefficient inputted into a complex multiplier, wherein the complex multiplier outputs a signal predicting value.