公开(公告)号：EP0570480A4

公开(公告)日：1994-07-06

申请号：EP92905667

申请日：1992-02-04

申请人： MOTOROLA INC

发明人： ECKLUND LAWRENCE M

IPC分类号： H03D3/24 ,  H03D5/00 ,  H04B1/06 ,  H04B1/16 ,  H04H20/88 ,  H03D3/22

CPC分类号： H03D3/241 ,  H03D5/00 ,  H04B1/1646

摘要： An improved AM-FM combined stereo receiver (100) is provided having a single processor (155) for removing, in the FM mode, arc-tangent distortion, and in the AM mode, to process the phase term from arc-tangent {L - R/1 + L + R} to determine {L - R/1 + L + R}. Further, the radio includes a single discriminator circuit (161, 137, 139) wherein, in the FM mode, the discriminator tank circuit (137, 139) is used to convert frequency deviation to baseband audio and, in the AM mode, the discriminator tank circuit is used as the frequency-determining element for the voltage controlled oscillator (VCO) (161), the VCO being used to translate the intermediate frequency (IF) signal to baseband.