Methods and apparatus for reducing the average-to-minimum magnitude ratio of communications signals in communications transmitters
US8363752B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 1, 2009 |
| Grant date | Jan 29, 2013 |
| Priority date | — |
| Expiry date | Aug 8, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/361
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A communications transmitter configured to reduce the average-to-minimum magnitude ratio (AMR) of a communications signal includes a symbol mapper, a pulse-shaping filter, an AMR reduction circuit, and a modulator. The symbol mapper operates to generate a sequence of symbols from a binary-source data stream containing a message to be transmitted, and the pulse-shaping filter generates a baseband signal based on the sequence of symbols. The AMR reduction circuit is configured to compare magnitudes of samples of the baseband signal to a time-varying low-magnitude threshold, and modify the baseband signal to produce a modified baseband signal having a reduced AMR if a sample of the baseband signal is determined to have a magnitude less than the time-varying low-magnitude threshold. Finally, the modulator operates to modulate a carrier signal based on the modulation information contained in the modified baseband signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.