EP-4740372-A1 - MULTI-MILLISECOND RANGING IN ULTRA-WIDEBAND SYSTEMS

Abstract

A method of receiving a plurality of multi-millisecond (MMS) fragments in an ultra-wideband (UWB) device is disclosed. The method includes processing each of the plurality of MMS fragments based on an initial range of CFO values and a coarse timing estimate. For each MMS fragment, the processing comprises performing coherent fragment accumulation using parallel processing for a plurality of carrier slice CFO values within the initial range, resulting in a number of fragment-accumulators; and applying parallel fragment-dependent timing drift correction to each corresponding fragment-accumulator, yielding a plurality of timing-corrected fragment-accumulators, one for each of a plurality of timing slice CFO hypotheses. The method may further include, for each of the timing slice CFO hypotheses, combining the plurality of timing-corrected fragment-accumulators to yield a plurality of combined final accumulators. The method may further include identifying one of the plurality of combined final accumulators as a selected final accumulator.

Inventors

• MCLAUGHLIN, MICHAEL
• NIEWCZAS, JAROSLAW
• VERSO, BILLY
• MURRAY, CARL

Assignees

• Qorvo US, Inc.

Dates

Publication Date

20260513

Application Date

20240607

Claims (20)

1. 1. A method of receiving a plurality of multi-millisecond (MMS) fragments in an ultra- wideband (UWB) device, the method comprising: establishing an initial range of carrier frequency offset (CFO) values; establishing a coarse timing estimate of a start of the plurality of MMS fragments; and processing each of the plurality of MMS fragments based on the initial range of CFO values and the coarse timing estimate, wherein for each MMS fragment, the processing comprises: performing coherent fragment accumulation using parallel processing for a plurality of carrier slice CFO values within the initial range, resulting in a number of fragment- accumulators; and applying parallel fragment-dependent timing drift correction to each corresponding fragment- accumulator, yielding a plurality of timing-corrected fragment- accumulators, one for each of a plurality of timing slice CFO hypotheses; after processing the plurality of MMS fragments, for each of the timing slice CFO hypotheses, combining the plurality of timing-corrected fragment-accumulators to yield a plurality of combined final accumulators; and identifying one of the plurality of combined final accumulators as a selected final accumulator based on at least one criteria.
2. 2. The method of claim 1, wherein establishing the initial range of CFO values comprises: pairing the UWB device with another UWB device by way of transmitting or receiving UWB packets; estimating a coarse CFO estimate during the pairing; and establishing the initial range of CFO values based on the coarse CFO estimate and an error tolerance.
3. 3. The method of claim 1, wherein the performing coherent fragment accumulation comprises: providing a signal to a first accumulator to generate a first fragment-accumulator; and providing the signal to a second accumulator to generate a second fragmentaccumulator.
4. 4. The method of claim 3, wherein the applying parallel fragment-dependent timing drift correction further comprises: providing the first fragment-accumulator to a first plurality of timing processing units to generate a first plurality of outputs; and providing the second fragment-accumulator to a second plurality of timing processing units to generate a second plurality of outputs.
5. 5. The method of claim 1 , wherein the identifying one of the plurality of final accumulators is based on which of the plurality of combined final accumulators has a largest magnitude.
6. 6. The method of claim 5, wherein the largest magnitude is compared to a threshold.
7. 7. The method of claim 1, wherein the combining the timing-corrected fragmentaccumulators comprises summing absolute values of the fragment- accumulators.
8. 8. The method of claim 1 , wherein the combining the timing-corrected fragmentaccumulators comprises coherently combining the timing-corrected fragment-accumulators.
9. 9. The method of claim 1 , wherein the combining the timing-corrected fragmentaccumulators comprises estimating a phase change between fragments using a selected peak of fragment-accumulation signals and compensating for the phase change in combining the timing-corrected fragment-accumulators.
10. 10. The method of claim 1, wherein establishing the initial range of CFO values comprises: receiving a message using a type of communication other than UWB communication; determining a coarse CFO estimate from the message; and establishing the initial range of CFO values based on the coarse CFO estimate and an error tolerance.
11. 11. The method of claim 1 , wherein establishing the initial range of CFO values comprises: exchanging messages with another device using a type of communication other than UWB communication, wherein a clock for the type of communication in the UWB device is coupled to a clock used for UWB communication, and wherein the initial range of CFO values is based on the messages.
12. 12. The method of claim 1, wherein the selected final accumulator is used in a ranging application.
13. 13. The method of claim 1, wherein a duration of each MMS fragment is less than 64 microseconds.
14. 14. A wireless apparatus comprising: a radio frequency circuit configured to downconvert a plurality of ultra-wideband (UWB) multi-millisecond (MMS) fragments to generate a plurality of received MMS fragments; a plurality of accumulators configured to process each of the plurality of received MMS fragments using a plurality of carrier slice CFO values, wherein the accumulators and carrier slice CFO values are in one-to-one correspondence, resulting in a number of fragmentaccumulation signals per fragment; a plurality of banks of timing processing units, wherein each of the plurality of accumulators is coupled to a corresponding bank of timing processing units, and wherein, for each fragment, the plurality of banks of timing processing units apply parallel fragmentdependent timing offset correction to each corresponding fragment-accumulation signal, yielding timing-corrected fragment-accumulators, one for each of a plurality of timing slice CFO hypotheses; and a processor configured to: combine the timing-corrected fragment-accumulators for each of the plurality of timing slice CFO hypotheses over the plurality of MMS fragments to yield a plurality of combined final accumulators; and identify one of the plurality of combined final accumulators as a selected final accumulator based on at least one criteria.
15. 15. The wireless apparatus of claim 14, wherein the plurality of carrier slice CFO values is within an initial range of CFO values established by pairing the wireless apparatus with another wireless UWB device.
16. 16. The wireless apparatus of claim 14, wherein the identifying one of the plurality of final accumulators is based on which of the plurality of combined final accumulators has a largest magnitude.
17. 17. The wireless apparatus of claim 14, wherein the combining the timing-corrected fragment- accumulators comprises summing absolute values of the fragment-accumulators.
18. 18. A wireless communication device comprising: a memory configured to store an initial range of carrier frequency offset (CFO) values and a coarse timing estimate of a start of a plurality of multi-millisecond (MMS) fragments; an ultra-wideband (UWB) receiver configured to receive the plurality of MMS fragments, wherein for each MMS fragment, the receiving comprises: performing coherent fragment accumulation using parallel processing for a plurality of carrier slice CFO values within the initial range, resulting in a number of fragment- accumulators; and applying parallel fragment-dependent timing drift correction to each corresponding fragment- accumulator, yielding a plurality of timing-corrected fragment-accumulators, one for each of a plurality of timing slice CFO hypotheses, and a processor configured to: after receiving the plurality of MMS fragments, for each of the plurality of timing slice CFO hypotheses, combine the timing-corrected fragment-accumulators yielding a plurality of combined final accumulators; and identify one of the plurality of combined final accumulators as a selected final accumulator based on at least one criteria.
19. 19. The wireless communication device of claim 18, wherein the performing coherent fragment accumulation comprises: providing a signal to a first accumulator to generate a first fragment-accumulator; and providing the signal to a second accumulator to generate a second fragmentaccumulator.
20. 20. The wireless communication device of claim 19, wherein the applying parallel fragment-dependent timing drift correction further comprises: providing the first fragment-accumulator to a first plurality of timing processing units to generate a first plurality of outputs; and providing the second fragment-accumulator to a second plurality of timing processing units to generate a second plurality of outputs.

Description

MULTI-MILLISECOND RANGING IN ULTRA-WIDEBAND SYSTEMS CROSS-REFERENCE TO RELATED APPLICATIONS [0001] The present application claims the benefit of U.S. Provisional App. No. 63/512,372, entitled “Multi-Millisecond Ranging in Ultra-Wideband” and filed on July 7, 2023, and U.S. Provisional App. No. 63/555,742, entitled “Multi-Millisecond Ranging in Ultra-Wideband Systems” and filed on February 20, 2024, both of which are incorporated by reference herein in their entireties. TECHNICAL FIELD [0002] The present disclosure relates generally to ranging in ultra-wideband systems, and, more specifically, to systems, methods, and devices for ranging in ultra- wideband systems that use multi-millisecond transmissions. BACKGROUND [0003] Ranging of ultra-wideband (UWB) devices is limited by the regulatory requirements on average transmit power (such as transmit power per unit of time, such as a millisecond (ms)). For example, due to the duration of transmission of conventional UWB transmissions, such as High Rate Pulse Repetition Frequency (HRP) UWB mode transmissions, each transmission may occur at a relatively low power in order to comply with average power requirements, making it difficult to perform ranging with sufficient accuracy at increasing distances/ranges. [0004] FIG. 1 illustrates known packet configurations for HRP UWB, according to some aspects of the present disclosure. The fields of the packet configurations are illustrated, with the synchronization field denoted by SYNC, the state-of-frame delimiter denoted by SFD, the PHY (physical layer) header represented by PHR, the physical layer payload represented by PHY Payload, and the Scrambled Timestamp Sequence field represented by STS. These packet configurations are transmitted with a relatively low power, such as to comply with average power requirements, making it difficult to perform ranging with sufficient accuracy at increasing distances/ranges. [0005] Thus, there remains a need for techniques that work at increased ranges, while still complying with regulatory requirements on average transmit power. SUMMARY [0006] Embodiments of the present disclosure include systems, devices, and methods of communication multi-millisecond (MMS) fragments. [0007] In an exemplary aspect, method of receiving a plurality of MMS fragments in a UWB device is disclosed. The method includes establishing an initial range of carrier frequency offset (CFO) values, and establishing a coarse timing estimate of a start of the plurality of MMS fragments. The method may further include processing each of the plurality of MMS fragments based on the initial range of CFO values and the coarse timing estimate. For each MMS fragment, the processing comprises performing coherent fragment accumulation using parallel processing for a plurality of carrier slice CFO values within the initial range, resulting in a number of fragment- accumulators; and applying parallel fragmentdependent timing drift correction to each corresponding fragment-accumulator, yielding a plurality of timing-corrected fragment- accumulators, one for each of a plurality of timing slice CFO hypotheses. The method may further include after processing the plurality of MMS fragments, for each of the timing slice CFO hypotheses, combining the plurality of timing- corrected fragment- accumulators to yield a plurality of combined final accumulators. The method may further include identifying one of the plurality of combined final accumulators as a selected final accumulator based on at least one criteria. [0008] In another exemplary aspect, a wireless apparatus is disclosed. The wireless apparatus includes a radio frequency circuit configured to downconvert a plurality of UWB MMS fragments to generate a plurality of received MMS fragments. The wireless apparatus may further include a plurality of accumulators configured to process each of the plurality of received MMS fragments using a plurality of carrier slice CFO values, wherein the accumulators and carrier slice CFO values are in one-to-one correspondence, resulting in a number of fragment-accumulation signals per fragment. The wireless apparatus may further include a plurality of banks of timing processing units, wherein each of the plurality of accumulators is coupled to a corresponding bank of timing processing units, and wherein, for each fragment, the plurality of banks of timing processing units apply parallel fragmentdependent timing offset correction to each corresponding fragment-accumulation signal, yielding timing-corrected fragment-accumulators, one for each of a plurality of timing slice CFO hypotheses. The wireless apparatus may further include a processor configured to combine the timing-corrected fragment-accumulators for each of the plurality of timing slice CFO hypotheses over the plurality of MMS fragments to yield a plurality of combined final accumulators; and identify one of the plurality of combined final accumulators as a selected final accumulat