Cell organization and transmission schemes in a wide area positioning system (WAPS)
First Claim
1. A position location system comprising:
- a plurality of transmitters that each broadcast a plurality of positioning signals,wherein each positioning signal of the plurality of positioning signals comprises a pseudorandom ranging signal,wherein, during an interval of time, at least two positioning signals are transmitted concurrently, each by a different member of the plurality of transmitters,wherein the at least two positioning signals have different carrier frequencies offset from one another by an offset that is less than or equal to twenty-five (25) percent of the bandwidth of each positioning signal of the at least two positioning signals,wherein each carrier frequency is the sum of a base frequency plus an element of a set of frequency offsets, and each of the frequency offsets in the set of frequency offsets is a multiple of a minimum nonzero offset,wherein the set of frequency offsets corresponds to 0, k0R+R/Q, 2 k0R+2R/Q, 3 k0R+3R/Q . . . , (Q−
1)k0R+(Q−
1)R/Q, where R represents PN frame rate, k0 represents a nonzero integer, and Q represents an integer equal to the number of frequency offsets in the set of frequency offsets.
4 Assignments
0 Petitions
Accused Products
Abstract
A position location system comprises transmitters that broadcast positioning signals. Each broadcasted positioning signal comprises a pseudorandom ranging signal. The position location system includes a remote receiver that acquires and measures the time of arrival of the positioning signals received at the remote receiver. During an interval of time, at least two positioning signals are transmitted concurrently by the transmitters and received concurrently at the remote receiver. The two positioning signals have carrier frequencies offset from one another by an offset that is less than approximately twenty-five percent of the bandwidth of each positioning signal of the two positioning signals. Cross-interference between the positioning signals is reduced by tuning the remote receiver to a frequency of a selected signal of the two positioning signals and correlating the selected signal with a reference pseudorandom ranging signal matched to a transmitted pseudorandom ranging signal of the selected signal.
219 Citations
31 Claims
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1. A position location system comprising:
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a plurality of transmitters that each broadcast a plurality of positioning signals, wherein each positioning signal of the plurality of positioning signals comprises a pseudorandom ranging signal, wherein, during an interval of time, at least two positioning signals are transmitted concurrently, each by a different member of the plurality of transmitters, wherein the at least two positioning signals have different carrier frequencies offset from one another by an offset that is less than or equal to twenty-five (25) percent of the bandwidth of each positioning signal of the at least two positioning signals, wherein each carrier frequency is the sum of a base frequency plus an element of a set of frequency offsets, and each of the frequency offsets in the set of frequency offsets is a multiple of a minimum nonzero offset, wherein the set of frequency offsets corresponds to 0, k0R+R/Q, 2 k0R+2R/Q, 3 k0R+3R/Q . . . , (Q−
1)k0R+(Q−
1)R/Q, where R represents PN frame rate, k0 represents a nonzero integer, and Q represents an integer equal to the number of frequency offsets in the set of frequency offsets. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31)
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Specification