Patent · US Expired

Frequency offset method and apparatus for use in a transceiver

US5715520A · kind A · utility

6Cited by
12References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 20, 1995
Grant dateFeb 3, 1998
Priority date
Expiry dateJan 20, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B1/50
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

The radio frequency transceiver was developed for use in a time division duplex (TDD) radiotelephone communication system. The transceiver includes a local oscillator which generates at least two local oscillator signals at different times. Each local oscillator signal has a unique frequency. During a first time period, the radio frequency transceiver receives a radio frequency signal. The first radio frequency signal is combined with one of the local oscillator signals, forming an intermediate frequency signal. During a second time period and substantially during the first time period, the transceiver generates a frequency offset signal. The frequency offset signal is combined with the second local oscillator signal, forming a second radio frequency signal. The intermediate frequency signal and the offset frequency signal are designed to have different frequencies to avoid the self-quieting problem inherent in a TDD communication system.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.