Dual channel superheterodyne receiver

• US 6,259,902 B1
• Filed: 10/29/1998
• Issued: 07/10/2001
• Est. Priority Date: 10/29/1998
• Status: Expired due to Term

• Current Assignee: Apple Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Callaway, Edgar Herbert Jr., Siomkos, John Robert
• Primary Examiner(s): Hunter, Daniel
• Assistant Examiner(s): LE, LANA N
• Application Number:
  US09/181,760
• Time in Patent Office: 985 Days
• Field of Search: 455/190.1, 455/196.1, 455/189.1, 455/180.1, 455/180.2, 455/180.3, 455/188.1, 455/188.2, 455/199.1, 455/280, 455/338, 455/339, 455/553, 455/552
• US Class Current: 455/190.1
• CPC Class Codes: H04B 1/18 Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H
• CPC Class Codes: H04B 1/28 the receiver comprising at least one semiconductor device having three or more electrodes

Abstract

A dual channel receiver (100) includes a front end bandpass filter (120) that has a front end bandwidth, a first mixer (130), a second mixer (135), and two essentially identical receiver back ends (190, 195). The front end bandpass filter splits a received signal into a first signal (121) and a second signal (122) of essentially equal signal strengths and provides out of band isolation between first and second signal outputs (123, 124). The first mixer is coupled to the first signal and to a high side injection signal (131), and generates a first mixer output signal (132). The second mixer is coupled to the second signal and to a low side injection signal (136), and generates a second mixer output signal (137). Each of the two essentially identical receiver back ends is coupled to one of the first and second mixer output signals.

Claims

1. A dual channel receiver, comprising:

a front end bandpass filter that has a front end bandwidth, that splits a received signal into a first signal and a second signal of essentially equal signal strengths, and that provides out of band isolation between first and second signal outputs at which the first and second signals are provided;

a first mixer coupled to the first signal and coupled to a high side injection signal having an injection frequency, INJ1, outside the front end bandwidth, the first mixer generating a first mixer output signal substantially at an intermediate frequency (IF);

second mixer coupled to the second signal and counled to a low side injection signal having an injection frequency, INJ2, outside the front end bandwidth, the second mixer generating a second mixer output signal substantially at the IF;

a first second stage mixer having a high side second stage injection signal that generates a first second stage mixer output signal at a second intermediate frequency; and

a second second stage mixer having a low side second stage injection signal that generates a second mixer output signal at the second intermediate frequency.