Patent ID: 6957055
Filing Date: 2005-10-18
Classification: H03D

Abstract:
1. A double balanced mixer for mixing an RF signal with a local oscillator signal to provide at an intermediate frequency signal comprising: a) a local oscillator terminal, an RF terminal and an intermediate frequency terminal; b) a first field effect transistor having a first gate, a first drain and a first source; c) a second field effect transistor having a second gate, a second drain and a second source, the first drain connected to the second drain; d) a third field effect transistor having a third gate, a third drain and a third source, the first source connected to the third source, the third gate connected to the second gate; e) a fourth field effect transistor having a fourth gate, a fourth drain and a fourth source, the third drain connected to the fourth drain, the second source connected to the fourth source, the first gate connected to the fourth gate; f) a local oscillator balun transformer connected between the local oscillator terminal and the junction of the first and fourth gates and the junction of the second and third gates; g) an intermediate frequency balun transformer connected between the junction of the first and second drains, the junction of the third and fourth drains and the intermediate frequency terminal; and h) a RF balun transformer coupled between the intermediate frequency balun transformer and the RF terminal.