One frequency repeater for a digital microwave radio system with cancellation of transmitter-to-receiver interference
US4701935A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 9, 1986 |
| Grant date | Oct 20, 1987 |
| Priority date | — |
| Expiry date | Jan 9, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B7/15585
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A digital microwave radio repeater using the same carrier frequency for the transmitter and the receiver carriers for improving the frequency utilization efficiency. The transmitter-to-receiver interference signal is cancelled by producing an estimated-interference signal of the interference signal from the digital baseband signal by the use of a transversal filter and by subtracting the estimated-interference signal from the received signal. The estimated-interference signal is also produced by frequency shifting a digital modulated signal in the transmitter. The transmitter carrier frequency is locked to the receiver carrier frequency by the use of a phase-locking technique, so that the interference signal is reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.