Position determination with NRSC-5 digital radio signals
View Patent ↗Apparatus to determine the position of a user terminal, the apparatus having corresponding methods and computer-readable media, comprises: a receiver to receive, at the user terminal, a wireless NRSC-5 digital radio signal; and a pseudorange module to determine a pseudorange between the receiver and a transmitter of the NRSC-5 digital radio signal based on the NRSC-5 digital radio signal; wherein the position module determines the position of the user terminal based on the pseudorange and a location of the transmitter.
1. An apparatus to determine the position of a user terminal, comprising:
a receiver configured to receive, at the user terminal, a wireless digital radio signal;
a pseudorange module configured to determine a pseudorange between the receiver and a transmitter of the digital radio signal based on the digital radio signal; and
a position module configured to determine the position of the user terminal based on the pseudorange and a location of the transmitter;
wherein the digital radio signal comprises a NRSC-5 signal, wherein said NRSC-5 signal is modulated using orthogonal frequency division multiplexing (OFDM) and is composed of a plurality of adjacent narrowband subcarriers, and further comprising:
a correlator configured to correlate the digital radio signal with a reference waveform;
wherein the pseudorange module is configured to determine the pseudorange based on an output of the correlator.
2. The apparatus of claim 1 , further comprising:
a signal generator configured to generate the reference waveform.
3. The apparatus of claim 2 :
wherein the receiver is configured to receive control data; and
wherein the signal generator is configured to generate the reference waveform based on the control data.
4. The apparatus of claim 1 :
wherein, to determine the position of the user terminal, the position module
determines an offset between a local time reference in the user terminal and a master time reference, and
determines the position of the user terminal based on the pseudorange, the location of the transmitter, and the offset.
5. The apparatus of claim 1 , wherein the receiver, the pseudorange module, and the position module are installed in the user terminal.
6. A method for determining the position of a user terminal, comprising:
receiving, at the user terminal, a wireless digital radio signal;
determining a pseudorange between the receiver and a transmitter of the digital radio signal based on the digital radio signal; and
determining the position of the user terminal based on the pseudorange and a location of the transmitter;
wherein the digital radio signal comprises a NRSC-5 signal, wherein said NRSC-5 signal is modulated using orthogonal frequency division multiplexing (OFDM) and is composed of a plurality of adjacent narrowband subcarriers, and further comprising:
correlating the digital radio signal with a reference waveform;
wherein the pseudorange is determined based on an output of the correlating.
7. The method of claim 6 , further comprising:
generating the reference waveform.
8. The method of claim 7 , further comprising:
receiving control data; and
generating the reference waveform based on the control data.
9. The method of claim 6 , wherein determining the position of the user terminal further comprises:
determining an offset between a local time reference in the user terminal and a master time reference; and
determining the position of the user terminal based on the pseudorange, the location of the transmitter, and the offset.
10. Non-transitory computer-readable storage media embodying instructions executable by a computer to perform a method comprising:
determining a pseudorange between a receiver of a wireless digital radio signal and a transmitter of the digital radio signal based on the digital radio signal; and
determining a position of a user terminal based on the pseudorange and a location of the transmitter;
wherein the digital radio signal comprises a NRSC-5 signal, wherein said NRSC-5 signal is modulated using orthogonal frequency division multiplexing (OFDM) and is composed of a plurality of adjacent narrowband subcarriers, and wherein the method further comprises:
correlating the digital radio signal with a reference waveform;
wherein the pseudorange is determined based on an output of the correlating.
11. The non-transitory computer-readable media of claim 10 , wherein the method further comprises:
generating the reference waveform.
12. The non-transitory computer-readable media of claim 11 , wherein the method further comprises:
receiving control data; and
generating the reference waveform based on the control data.
13. The non-transitory computer-readable media of claim 10 , wherein determining the position of the user terminal comprises:
determining an offset between a local time reference in the user terminal and a master time reference; and
determining the position of the user terminal based on the pseudorange, the location of the transmitter, and the offset.