Digital post-detection FM spatial diversity combination circuit
US5402451A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 11, 1993 |
| Grant date | Mar 28, 1995 |
| Priority date | — |
| Expiry date | Jan 11, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B17/318
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A Digital Post-Detection (Post-Discriminator) FM spatial diversity combination circuit improves performance for fading channels typical of cellular radio operating environments. A feature of this system is its flexibility. The system can be configured to use signal quality information in a manner which is appropriate for a given radio environment. Also, the weighting information can be derived from various sources and then processed to accommodate various situations. This spatial combiner has the ability to perform as a "hybrid" combiner. For example, this circuit can combine signals from various receivers based on soft weighting information, as in a maximal ratio combiner, or on hard weighting information, as in a switching combiner. The basic circuit includes a normalizing circuit (21, 22, 23) which receives the digitized received signal strength indicator samples from each of first and second receivers (11, 12) and generates first and second weighting signals. A first multiplier (24) multiplies the digitized discriminator samples from the first receiver by the first weighting signal to generate a first weighted output signal. A second multiplier (25) multiplies the digitized dis…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.