Differential radio

• US 7,031,689 B2
• Filed: 11/13/2001
• Issued: 04/18/2006
• Est. Priority Date: 11/13/2001
• Status: Expired due to Fees

• Current Assignee: Avago Technologies Wireless IP Singapore Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies Wireless IP Singapore Pte Limited (Broadcom, Inc.)
• Inventors: Frank, Michael L.
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): Sams, Matthew C
• Application Number:
  US10/008,492
• Publication Number:
  US 20030092408A1
• Time in Patent Office: 1,617 Days
• Field of Search: 455/130, 455/341, 455/323, 455/333, 333/133, 333/189
• US Class Current: 455/333
• CPC Class Codes: H04B 1/40 Circuits

Abstract

A cellphone handset may be excited in a completely differential mode. The antenna, e.g. a simple dipole or a minimal Yagi-Uda with a reflector, may be printed into the printed circuit board. A differential duplexer may be implemented using FBAR technology. The LNA (Low Noise Amplifier) and the PA (Power Amplifier) can both be differential.

Claims

1. A differential radio comprising:

a differential antenna having an input and an output;

a differential duplexer including film bulk acoustic resonators, generating tow receiving signals and receiving two transmitting signals, electrically connected to the input and output of the differential antenna;

a differential low noise amplifier, receiving the two receiving signals, generating two LNA signals, including,

an input matching network (IMN) having a differential input and a first and second IMN output;

a first capacitor, connected to the drain of the first FET;

a second FET, having a gate connected to the first capacitor;

a third FET, having a source connected to the source of the second FET;

an output matching network (OMN), having a first input connecting to the drain of the second FET and a second input connecting to the drain of the third FET;

a first inductor connecting between the source of the second FET and ground;

a second capacitor connected to the gate of the third FET;

a fourth FET having a drain connected to the second capacitor, a gate connected to the second IMN output, a source connected to the source of the first FET; and

a second inductor connects between the source of the first FET and ground;

a differential filter receiving the two LNA signals and generating a first differential filter signal;

a first differential mixer receiving the first differential signal and generating a first differential mixer output signal;

a signal, processing section, receiving the first differential mixer output signal, generating a conditioned differential signal;

a second differential mixer, receiving the conditioned differential signal, generating a second differential mixer output signal;

a second differential filter, receiving the second differential mixer output signal, generating a second differential filter signal; and

a differential power amplifier receiving the second differential filter signal and generating the two transmitting signals.

2. A differential radio as in claim 1, wherein the differential antenna is incorporated into a printed circuit board.