A set of single chip mult{functions has been developed at X bandfor sensor applications. This kind of circuits gathers all the necessary basic functions such as oscillators, buffer amplifiers, power dividers, modulators and mixers. The chosen technology is TCS standard process LN05 based on 0. 5pm implanted MESFET, via holes, air bridges and electron beam lithography. All of these circuits are working around 10GHz with more than 20% bandwidth. The transmitted output power is greater than lOdBm and the noisefigure is better than 7.5dB SSBfor an IF of 10MHz. The IF output can also be used at very low frequencies (from DC) and exhibits low noise with a typical value of-440dBm/Hz at IkHz.