Demodulating beidou GNSS signals
Assigneeu-blox AG
InventorZhenlan Cheng
Life of this patent
Estimating the term…
Abstract
A method and apparatus are provided for demodulating a B2b signal from a satellite in the BeiDou Navigation Satellite System. The method comprises tracking a first signal transmitted in a first GNSS operational band by the satellite, to estimate one or more parameters of the first signal; predicting, based on the estimated one or more parameters of the first signal, one or more parameters of the B2b signal transmitted by the satellite; and demodulating the B2b signal to obtain data bits of a data message modulated on the B2b signal by the satellite. The demodulating is based on the one or more predicted parameters of the B2b signal.
Claims9
A method for demodulating a B2b signal from a satellite in the BeiDou Global Navigation Satellite System (GNSS), the method comprising:
- tracking a first signal transmitted in a first GNSS operational band by the satellite, to estimate one or more parameters of the first signal;
- predicting, based on the estimated one or more parameters of the first signal, one or more parameters of the B2b signal transmitted by the satellite;
- demodulating the B2b signal to obtain data bits of a data message modulated on the B2b signal by the satellite,
- wherein the demodulating is based on the one or more predicted parameters of the B2b signal,
- wherein the one or more parameters of the first signal comprise a code phase of the first signal, and the one or more parameters of the B2b signal comprise a code phase of the B2b signal,
- wherein predicting the code phase of the B2b signal comprises adding or subtracting an offset to or from an estimated code phase of the first signal;
- and
- estimating a group delay difference between the first signal and the B2b signal,
- wherein the offset comprises or consists of the estimated group delay difference.
One or more tangible, non-transitory, computer-readable media storing instructions that, when executed by one or more machines, cause the one or more machines to perform operations comprising:
- track a first signal transmitted in a first BeiDou Global Navigation Satellite System (GNSS) operational band by a satellite, to estimate one or more parameters of the first signal;
- predict, based on the estimated one or more parameters of the first signal, one or more parameters of a B2b signal transmitted by the satellite;
- demodulate the B2b signal to obtain data bits of a data message modulated on the B2b signal by the satellite, wherein the demodulating is based on the one or more predicted parameters of the B2b signal,
- wherein the one or more parameters of the first signal comprise a code phase of the first signal, and the one or more parameters of the B2b signal comprise a code phase of the B2b signal;
- wherein predicting the code phase of the B2b signal comprises adding or subtracting an offset to or from an estimated code phase of the first signal;
- and
- estimating a group delay difference between the first signal and the B2b signal, wherein the offset comprises or consists of the estimated group delay difference.
A Global Navigation Satellite System (GNSS) receiver comprising:
- at least one tracking loop, configured to track a first signal transmitted in a first GNSS operational band by a satellite in the BeiDou GNSS, to estimate one or more parameters of the first signal;
- a prediction subsystem, configured to predict, based on the estimated one or more parameters of the first signal, one or more parameters of a B2b signal transmitted by the satellite;
- and
- a demodulator, configured to demodulate the B2b signal to obtain data bits of a data message modulated on the B2b signal by the satellite,
- wherein the demodulator is configured to demodulate the B2b signal based on the one or more predicted parameters of the B2b signal,
- wherein the one or more parameters of the first signal comprise a code phase of the first signal, and the one or more parameters of the B2b signal comprise a code phase of the B2b signal;
- wherein the prediction subsystem comprises an adder or a subtractor configured to predict the code phase of the B2b signal by adding or subtracting an offset to or from an estimated code phase of the first signal, and
- wherein the prediction subsystem comprises a group delay difference estimator configured to estimate a group delay difference between the first signal and the B2b signal, wherein the offset comprises or consists of the estimated group delay difference.
Dependencies are inferred from the claim text.