US 5,978,414 A · Transmission rate judging unit

Abstract

A method and system is disclosed for determining an actual transmission rate of an encoded communication which has been transmitted at one of a plurality of transmission rates. An encoded communication is decoded at the plurality of transmission rates to generate decoded signals and decoding parameters which indicate the reliability of the decoded signals. One or more candidate transmission rates are identified based upon said decoding reliability parameters. If there is only one candidate transmission rate, the actual transmission rate is determined to be that candidate transmission rate. If there is more than one candidate transmission rate, the decoded signals are reencoded at the candidate transmission rates at which they were decoded. The bits of the communication are then compared with the bits of the reencoded signals for each candidate transmission rate to determine the actual transmission rate. A method and system is further disclosed for determining threshold values for comparison with the decoding reliability parameters in identifying the candidate transmission rates. A method and system is further disclosed which determines those threshold values on the basis of detected reception conditions, including the relative strength of multipath component signals and the total received power in the communication.

Claims22

Dependent claims

A method for determining an actual transmission rate of an encoded communication transmitted at one of a plurality of transmission rates, comprising the steps of:

(a) decoding said encoded communication at said plurality of transmission rates to generate a plurality of decoded signals;
(b) determining a decoding reliability parameter corresponding to each of said decoded signals;
(c) identifying one or more candidate transmission rates at which said encoded communication has been reliably decoded based upon said decoding reliability parameters, wherein said identifying is performed by comparing said decoding reliability parameters with threshold values;
and
(d) determining said actual transmission rate from said one or more candidate transmission rates.

2 more elements

A spread spectrum communications receiver for demodulating and decoding a communication transmitted at any of a plurality of predetermined transmission rates, comprising:

a plurality of demodulation means for demodulating each of a plurality of multipath components of a communication signal;
means for combining said demodulated multipath components to produce a combined demodulated signal;
means for measuring reception conditions;
means responsive to said combined demodulated signal and said measured reception conditions for determining an actual transmission rate at which said communication was transmitted and for producing a decoded communication signal at said actual transmission rate.

1 more element

Dependencies are inferred from the claim text.

Transmission rate judging unit

Life of this patent

Transmission rate judging unit

Life of this patent

Abstract

Claims22