Digital reverse transmission frequency training method for time division duplex (TDD) communication system
US7209494B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2000 |
| Grant date | Apr 24, 2007 |
| Priority date | — |
| Expiry date | Feb 9, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2027/0077
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A Time Division Duplex (TDD), Code Division Multiple Access (CDMA) communication system includes a plurality of Customer Premises Equipment (CPE) and an Access Point (AP) that communicate through RF links. A CPE contains a receiver baseband subsystem and a transmitter baseband subsystem, and further contains receiver circuitry operable during a receive period for receiving an RF carrier from the AP and for deriving a receiver tracking signal that is indicative of a frequency and phase shift between the received RF carrier and a reference signal. The receiver circuitry further includes a frequency to phase accumulator (FPA) and a digital phase shifter (DPS) for correcting the frequency and phase of a receiver baseband signal by an amount and in a direction indicated by the receiver tracking signal. CPE transmitter circuitry is operable during a next transmission period for operating the FPA and DPS circuitry to correct the frequency of a transmitter baseband signal by an amount indicated by the receiver tracking signal, and in a direction opposite to the direction indicated by the receiver tracking signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.