System and method to optimize multicarrier communication
US8611439B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2007 |
| Grant date | Dec 17, 2013 |
| Priority date | — |
| Expiry date | Aug 30, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L5/006
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A system and method for allocating transmitter power to subcarriers of a multicarrier signal is provided. First, the subcarriers are transmitted with an initial set of power levels and an initial set of constellation assignments. Next, quantized SNR metric values are measured at the receiver for each subcarrier. The measured subcarrier quantized SNR metric is compared with the respective allocated constellation quantized SNR metric, for determining the excess SNR per subcarrier. The transmitter power of the subcarriers whose excess SNR is above a predetermined threshold is adjusted, while keeping the total transmitter power constant. The transmitter power may be adjusted for increasing throughput or robustness of the system. For increased accuracy, several training frames may be used. Advantageously, only constellations equally spaced, such as square or cross constellations, are used. According to a preferred embodiment, OFDM/DMT multicarrier system use IFFT prescalers in the transmitter power adjustment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.