Method and apparatus for performing rate determination
US5872775A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1996 |
| Grant date | Feb 16, 1999 |
| Priority date | — |
| Expiry date | Oct 30, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/0262
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A system and method for determining the transmission rate of a data signal at a receiver of a variable rate communications system. A vocoder at a transmitter encodes a frame of data into symbols according to one of a set of discrete data rates. When the data rate is lower than the maximum, each symbol is repeated a number of times as required to achieve a constant number of symbols in each frame. The data signal is transmitted at a power proportional to the data rate of the frame. A reference signal is also transmitted. The reference signal is transmitted at a constant power. Further, the data signal has the same carrier frequency as a reference signal so that they exhibit the same fading characteristics as they are transmitted through the channel. At a receiver, the power of the data signal and the power of reference signal are measured as received. The ratio of the power of the data signal to the power of the reference signal is compared with a predetermined ratio of the power of a maximum rate data signal to the power of the reference signal. The result of the comparison will indicate the encoded data rate of the received frame of data. The rate determined by the rate determinat…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.