Single frequency time division duplex transceiver
US5123008A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 13, 1989 |
| Grant date | Jun 16, 1992 |
| Priority date | — |
| Expiry date | Mar 13, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/408
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A time division duplex transceiver incorporating a dual conversion superheterodyne receiver, and in which the first receiver local oscillator doubles as the frequency source for the transmitter. The oscillator is a voltage controlled oscillator VCO forming part of a mixer-type phase locked loop. Frequency deviation in the loop is achieved by mixing the VCO output with a selected harmonic of the output of the second receiver local oscillator. The reference oscillator is a crystal controlled oscillator whose output is switched as between transmit mode and receive mode at a switch before being passed to the loop phase detector. The transceiver is able to rapidly and repeatedly alternate between transmit and receive modes and is thus well suited to time division multiplex operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.