Beam index and link index dependent sequence generation for positioning beacon
Disclosed are techniques for generating a positioning beacon sequence suitable for use in a wireless network that utilizes beamformed communication. More particularly, the positioning beacon sequence may be generated based on a first sequence that depends on a link identifier and does not depend on a beam index assigned to a beam used to transmit the positioning beacon in combination with a second sequence that depends on the beam index and does not depend on the link identifier. For example, the first sequence and the second sequence may be XORed to obtain the final beacon sequence, or the first sequence and the second sequence may be modulated and multiplied to obtain the final beacon sequence. Furthermore, in practice, the beacon sequence may be generated using a pseudo-random sequence generator initialized with a seed in which the link identifier and the beam index are treated as separate subcomponents.
1. A method for generating a positioning beacon sequence, comprising:
determining a first sequence associated with a positioning beacon, wherein the first sequence is dependent on a link identifier and independent of a beam index assigned to a beam used to transmit the positioning beacon;
determining a second sequence associated with the positioning beacon, wherein the second sequence is dependent on the beam index assigned to the beam used to transmit the positioning beacon and independent of the link identifier;
generating the positioning beacon sequence based on the first sequence and the second sequence; and
performing a positioning operation using the positioning beacon sequence.
2. The method recited in claim 1 , wherein the positioning beacon sequence comprises an exclusive or (XOR) of the first sequence and the second sequence.
3. The method recited in claim 1 , wherein generating the positioning beacon sequence comprises:
modulating the first sequence;
modulating the second sequence; and
multiplying the modulated first sequence and the modulated second sequence.
4. The method recited in claim 1 , wherein generating the positioning beacon sequence comprises:
initializing a pseudo-random sequence generator using a seed that combines a first value dependent on the link identifier with a second value dependent on the beam index, wherein the first value does not depend on the beam index, and wherein the second value does not depend on the link identifier; and
generating the positioning beacon sequence using the initialized pseudo-random sequence generator.
5. The method recited in claim 4 , wherein the seed is computed based on an exclusive or (XOR) between the first value and the second value.
6. The method recited in claim 4 , wherein the seed is computed based on an arithmetic addition of the first value and the second value.
7. The method recited in claim 4 , wherein the seed further combines the first value dependent on the link identifier and the second value dependent on the beam index with a third value that depends on a transmission time for the positioning beacon.
8. The method recited in claim 4 , wherein one or more of the first value or the second value further depends on a transmission time for the positioning beacon.
9. The method recited in claim 1 , wherein the positioning beacon sequence is a Gold sequence.
10. The method recited in claim 1 , wherein the positioning beacon sequence is a maximum length (M) sequence.
11. The method recited in claim 1 , wherein the positioning beacon sequence is generated by a transmitter device, and wherein performing the positioning operation comprises transmitting the positioning beacon sequence.
12. The method recited in claim 1 , wherein the positioning beacon sequence is generated by a receiver device, wherein performing the positioning operation comprises using the positioning beacon sequence as a reference to receive and measure a positioning beacon transmission from a transmitter device, and wherein the positioning beacon transmission carries the positioning beacon sequence.
13. An apparatus, comprising:
a memory; and
at least one processor coupled to the memory, the at least one processor configured to:
determine a first sequence and a second sequence associated with a positioning beacon, the first sequence dependent on a link identifier and independent of a beam index assigned to a beam used to transmit the positioning beacon, the second sequence dependent on the beam index and independent of the link identifier,
generate a positioning beacon sequence based on the first sequence and the second sequence, and
perform a positioning operation using the positioning beacon sequence.
14. The apparatus recited in claim 13 , wherein the positioning beacon sequence comprises an exclusive or (XOR) of the first sequence and the second sequence.
15. The apparatus recited in claim 13 , wherein the memory and the at least one processor are further configured to:
modulate the first sequence;
modulate the second sequence; and
multiply the modulated first sequence and the modulated second sequence to generate the positioning beacon sequence.
16. The apparatus recited in claim 13 , wherein the memory and the at least one processor are further configured to:
initialize a pseudo-random sequence generator using a seed that combines a first value dependent on the link identifier with a second value dependent on the beam index, wherein the first value does not depend on the beam index, wherein the second value does not depend on the link identifier, and
use the initialized pseudo-random sequence generator to generate the positioning beacon sequence.
17. The apparatus recited in claim 16 , wherein the seed is computed based on an exclusive or (XOR) between the first value and the second value.
18. The apparatus recited in claim 16 , wherein the seed is computed based on an arithmetic addition of the first value and the second value.
19. The apparatus recited in claim 16 , wherein the seed further combines the first value dependent on the link identifier and the second value dependent on the beam index with a third value that depends on a transmission time for the positioning beacon.
20. The apparatus recited in claim 19 , wherein one or more of the first value or the second value further depends on the transmission time for the positioning beacon.
21. The apparatus recited in claim 13 , wherein the positioning beacon sequence is a Gold sequence.
22. The apparatus recited in claim 13 , wherein the positioning beacon sequence is a maximum length (M) sequence.
23. The apparatus recited in claim 13 , wherein the apparatus comprises a transmitter device, and wherein the memory and the at least one processor being configured to performing the positioning operation comprises the memory and the at least one processor configured to cause the apparatus to transmit the positioning beacon sequence.
24. The apparatus recited in claim 13 , wherein the apparatus is a receiver device, wherein the memory and the at least one processor being configured to perform the positioning operation comprises the memory and the at least one processor being configured to use the positioning beacon sequence as a reference to receive and measure a positioning beacon transmission from a transmitter device, and wherein the positioning beacon transmission carries the positioning beacon sequence.
25. An apparatus, comprising:
means for determining a first sequence associated with a positioning beacon, wherein the first sequence is dependent on a link identifier and independent of a beam index assigned to a beam used to transmit the positioning beacon;
means for determining a second sequence associated with the positioning beacon, wherein the second sequence is dependent on the beam index assigned to the beam used to transmit the positioning beacon and independent of the link identifier;
means for generating a positioning beacon sequence based on the first sequence and the second sequence; and
means for performing a positioning operation using the positioning beacon sequence.
26. The apparatus recited in claim 25 , wherein the positioning beacon sequence comprises an exclusive or (XOR) of the first sequence and the second sequence.
27. The apparatus recited in claim 25 , wherein the means for generating the positioning beacon sequence comprises:
means for modulating the first sequence;
means for modulating the second sequence; and
means for multiplying the modulated first sequence and the modulated second sequence.
28. The apparatus recited in claim 25 , wherein the means for generating the positioning beacon sequence comprises:
means for initializing a pseudo-random sequence generator using a seed that combines a first value dependent on the link identifier with a second value dependent on the beam index, wherein the first value does not depend on the beam index, and wherein the second value does not depend on the link identifier; and
means for generating the positioning beacon sequence using the initialized pseudo-random sequence generator.
29. A non-transitory computer-readable medium having computer-executable instructions recorded thereon, the computer-executable instructions configured to cause a processor to:
determine a first sequence associated with a positioning beacon, wherein the first sequence is dependent on a link identifier and independent of a beam index assigned to a beam used to transmit the positioning beacon;
determine a second sequence associated with the positioning beacon, wherein the second sequence is dependent on the beam index assigned to the beam used to transmit the positioning beacon and independent of the link identifier;
generate a positioning beacon sequence based on the first sequence and the second sequence; and
perform a positioning operation using the positioning beacon sequence.
30. The non-transitory computer-readable medium recited in claim 29 , wherein the positioning beacon sequence comprises an exclusive or (XOR) of the first sequence and the second sequence.