Kit of a local oscillator of an airborne VHF multimode communication transceiver

• US 20040121747A1
• Filed: 12/24/2002
• Published: 06/24/2004
• Est. Priority Date: 12/24/2002
• Status: Abandoned Application

• Current Assignee: Cheu-Ming Bow, Chiu-Chin Liao, Hong-Ji Chen, Lee-Tung Wei, Sy-Kang Shen, Ying A.N. Liu
• Original Assignee: Cheu-Ming Bow, Chiu-Chin Liao, Hong-Ji Chen, Lee-Tung Wei, Sy-Kang Shen, Ying A.N. Liu
• Inventors: Chen, Hong-Ji, Bow, Cheu-Ming, Wei, Lee-Tung, Liao, Chiu-Chin, Liu, Ying An, Shen, Sy-Kang
• Application Number:
  US10/327,177
• Publication Number:
  US 20040121747A1
• Time in Patent Office: Days
• US Class Current: 455/141
• CPC Class Codes: H04B 1/403 using the same oscillator for generating both the transmitter frequency and the receiver local oscillator frequency

Abstract

The invention relates to a kit of a local oscillator of an airborne VHF multimode communication transceiver. The local oscillator of the airborne VHF multimode communication transceiver comprises a temperature compensated crystal local oscillator, a direct digital synthesizer (DDS) and an input/output interface.

Claims

1. A local oscillator circuit assembly of airborne VHF multimode communication transceiver comprising a temperature compensated crystal local oscillator, a direct digital synthesizer (DDS) and an input/output interface.

2. The local oscillator circuit assembly in claim 1, wherein the local oscillator circuit assembly adopts a temperature compensated crystal local oscillator to generate the second local oscillator signal for the airborne VHF multimode communication transceiver.

3. The local oscillator circuit assembly as in claim 1, wherein the local oscillator circuit assembly adopts a direct digital synthesizer (DDS) to output the first local oscillator signal for airborne VHF multimode communication transceiver.

4. The local oscillator circuit assembly as in claim 1, wherein the local oscillator circuit assembly uses a temperature compensated crystal local oscillator to provide system clock signal for the direct digital synthesizer (DDS) to generate first local oscillator signal.

5. A system method for assembling a local oscillator circuit assembly of an airborne VHF multimode communication transceiver comprising the steps of:

(a) coupling a temperature compensated crystal oscillator, which generates a low noise second oscillator signal, to a digital type receiver'"'"'s second mixer stage for demodulation;

(b) coupling said second oscillator signal to a direct digital synthesizer (DDS) for use as system clock signal; and

(c) Coupling the second oscillator to a digital type transmitter'"'"'s first mixer stage for modulation, a direct digital synthesizer (DDS) via an input/output interface and an external microprocessor (not shown) control to generate a first local oscillator signal coupled to a digital type receiver'"'"'s first mixer stage for demodulation and a digital type transmitter'"'"'s second mixer stage for modulation respectively.