发明名称 |
Harmonic rejection gated-switching mixer |
摘要 |
Rejection of local oscillator harmonic response is provided in a mixing circuit with a pair of harmonic gating switches serially connected to the outputs of a balanced differential switching mixer and controlled by a gate clock signal having twice the frequency of a local oscillator signal controlling the switching mixer. An aperture or duty cycle of the gate clock signal determines which harmonic is rejected or suppressed, which is preferably a third and/or fifth harmonic since response of the balanced differential switching mixer to even harmonics is negligible. The resulting simple, efficient circuit is readily integrated directly into a phase-alternating mixer structure for a chopper-direct-conversion radio.
|
申请公布号 |
US7299025(B1) |
申请公布日期 |
2007.11.20 |
申请号 |
US20030457825 |
申请日期 |
2003.06.09 |
申请人 |
NATIONAL SEMICONDUCTOR CORPORATION |
发明人 |
WONG HEE;SCHWARTZ MICHAEL;BRAATZ JAMES;JU SHU-ING |
分类号 |
H04B1/06;H04B1/16;H04B7/00 |
主分类号 |
H04B1/06 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|