公开(公告)号：GB2347292B

公开(公告)日：2001-04-18

申请号：GB0003945

申请日：2000-02-18

Applicant: MOTOROLA INC

Inventor： PECKHAM DAVID SUTHERLAND ,  DING DAVID Z ,  SKUTTA FRANK ROBERT ,  JOHNSON JR ROBERT M

IPC: H03D7/12 ,  H04B1/40 ,  H04B1/26

Abstract: A multiple frequency band receiver (102) receives at least two frequency bands that are close but not adjacent. A first bandpass filter (304) passes signals in the first frequency band. A second bandpass filter (306) passes signals in the second frequency band. The first and second filters each attenuate signals between the first and second frequency band to at least a first level so as to provide selectivity in the frequency range between the first and second frequencies to prevent the signals between these frequency bands from being further processed by the communication device. A third filter (322) coupled to first and second filters passes signals in both the first and second frequency band and attenuates signals above the pass band of the higher of the first and second filters and below the lower of the first and second filters.

公开(公告)号：GB2347292A

公开(公告)日：2000-08-30

申请号：GB0003945

申请日：2000-02-18

Applicant: MOTOROLA INC

Inventor： PECKHAM DAVID SUTHERLAND ,  DING DAVID Z ,  SKUTTA FRANK ROBERT ,  JOHNSON JR ROBERT M

IPC: H03D7/12 ,  H04B1/40 ,  H04B1/26

Abstract: A multi-band receiver 102 has respective bandpass filters 306 and 304 for two closely spaced but distinct channels, e.g. 1.8 GHz DCS and 1.9 GHz PCS frequencies. A further bandpass filter 318 is coupled in series with a selected one of the filters 306 or 304, and has a passband which includes both reception bands. Sharing of the filter 318 between the two channels reduces cost and volume. The filter 318 may precede or follow the filters 306 and 304. A fourth filter 308 passes signals in a further band widely spaced from the other bands, e.g. a 900 MHz GSM band.