Random access method of devices with different path loss

• US 11,019,606 B2
• Filed: 10/03/2018
• Issued: 05/25/2021
• Est. Priority Date: 10/09/2014
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Li, Junyi, Lane, Frank Anton, Wang, Xiao Feng
• Primary Examiner(s): Zhu, Bo Hui A
• Application Number:
  US16/151,030
• Publication Number:
  US 20190037557A1
• Time in Patent Office: 965 Days
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 5/0092 Indication of how the channel is divided
• CPC Class Codes: H04W 4/50 Service provisioning or reconfiguring
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

A method, an apparatus, and a computer program product for wireless communication are provided. According to one embodiment, a method of operating a device includes: selecting a signal format from a plurality of signal formats, each of the plurality of signal formats corresponding to a respective coding and modulation scheme of a plurality of coding and modulation schemes; and sending a request for random access to a base station according to the selected signal format.

Claims

1. A method of operating a device, comprising:

selecting, by the device, a signal format for a request for random access, wherein the signal format is selected from a plurality of signal formats based on a transmission-power capability of the device, a path loss between the device and a base station, or both, each of the plurality of signal formats corresponding to a respective coding and modulation scheme of a plurality of coding and modulation schemes such that the signal format selected by the device corresponds to a first coding and modulation scheme of the plurality of coding and modulation schemes, wherein each of the plurality of signal formats corresponds to a respective time duration, wherein the time duration of each signal format is based on the respective coding and modulation scheme; and

sending, by the device, the request for random access to the base station according to the selected signal format, wherein the request includes a known preamble common to the plurality of signal formats.

2. The method of claim 1,

wherein each of the plurality of signal formats further corresponds to a predetermined set of non-overlapping time and frequency resources,

wherein the method further comprises selecting a time and frequency resource from the predetermined set of non-overlapping time and frequency resources corresponding to the signal format selected by the device, and

wherein sending the request comprises sending the request for random access using a selected time and frequency resource.

3. The method of claim 2, further comprising:

receiving a signal from the base station; and

recovering an allocation control message from the signal, wherein the allocation control message specifies the signal formats corresponding to the predetermined set of non-overlapping time and frequency resources.

4. The method of claim 1,

wherein the plurality of signal formats further corresponds to a predetermined set of time and frequency resources,

wherein the method further comprises selecting a time and frequency resource from the predetermined set of time and frequency resources, and

wherein sending the request comprises sending the request for random access using a selected time and frequency resource.

5. The method of claim 1, further comprising determining the path loss between the device and the base station, and wherein a first signal format for the request for random access is associated with a first time duration for transmission of the request for random access from the device to the base station and wherein a second different signal format for the request for random access is associated with a second longer time duration for transmission of the request for random access from the device to the base station.

6. The method of claim 5,

wherein the plurality of signal formats is for Orthogonal Frequency-Division Multiple Access (OFDMA) signals or Single-Carrier Frequency-Division Multiple Access (SC-FDMA) signals,

wherein the first time duration corresponds to a predetermined number of symbols, wherein a second time duration corresponds to a different number of symbols and

wherein a predetermined frequency bandwidth corresponds to a predetermined number of subcarriers.

7. The method of claim 5, further comprising storing the path loss at the device to facilitate a subsequent request for random access.

8. The method of claim 5,

wherein the coding and modulation scheme corresponding to the first signal format of the plurality of signal formats and the coding and modulation scheme corresponding to a second signal format of the plurality of signal formats are different from each other.

9. The method of claim 8,

wherein the signal format is selected such that a robustness of the coding and modulation scheme corresponding to the signal format selected by the device is commensurate with the path loss between the device and the base station.

10. The method of claim 9, wherein the signal format is selected further such that, if the path loss is less than a threshold value, the coding and modulation scheme corresponding to the signal format selected by the device is less robust than the coding and modulation scheme corresponding to the second signal format of the plurality of signal formats.

11. The method of claim 9, wherein the signal format is selected further such that, if the path loss is greater than a threshold value, the coding and modulation scheme corresponding to the signal format selected by the device is more robust than the coding and modulation scheme corresponding to the second signal format of the plurality of signal formats.

12. The method of claim 1, further comprising storing the signal format selected by the device to facilitate a subsequent request for random access.

13. The method of claim 1, wherein the request for random access is sent to facilitate sending of an Internet of Things (IoT) communication to the base station.

14. An apparatus for wireless communication of a device, comprising:

a memory; and

at least one processor coupled to the memory and configured to;

select a signal format for a request for random access, wherein the signal format is selected from a plurality of signal formats based on a transmission-power capability of the apparatus for wireless communication, a path loss between the apparatus and a base station, or both, each of the plurality of signal formats corresponding to a respective coding and modulation scheme of a plurality of coding and modulation schemes such that the signal format selected by the device corresponds to a first coding and modulation scheme of the plurality of coding and modulation schemes, wherein each of the plurality of signal formats corresponds to a respective time duration, wherein the time duration of each signal format is based on the respective coding and modulation scheme; and

send the request for random access to the base station according to the signal format selected by the device, wherein the request includes a known preamble common to the plurality of signal formats.

15. The apparatus of claim 14, wherein the processor is further configured to determine the path loss between the apparatus and the base station, and wherein a first signal format for the request for random access is associated with a first time duration for transmission of the request for random access from the apparatus to the base station and wherein a second different signal format for the request for random access is associated with a second longer time duration for transmission of the request for random access from the apparatus to the base station.

16. The apparatus of claim 14, wherein the signal format is selected such that a robustness of the coding and modulation scheme corresponding to the signal format selected by the device is commensurate with the path loss between the apparatus and the base station, and wherein the signal format is selected further such that, if the path loss is less than a threshold value, the coding and modulation scheme corresponding to the signal format selected by the device is less robust than the coding and modulation scheme corresponding to a second signal format of the plurality of signal formats.

17. The apparatus of claim 14,

wherein each of the plurality of signal formats further corresponds to a predetermined set of non-overlapping time and frequency resources,

wherein the at least one processor is further configured to select a time and frequency resource from the predetermined set of non-overlapping time and frequency resources corresponding to the signal format selected by the device, and

wherein sending the request comprises sending the request for random access using a selected time and frequency resource.

18. The apparatus of claim 17, wherein the at least one processor is further configured to:

receive a signal from the base station; and

recover an allocation control message from the signal, wherein the allocation control message specifies the signal formats corresponding to the predetermined set of non-overlapping time and frequency resources.

19. The apparatus of claim 14,

wherein the plurality of signal formats further corresponds to a predetermined set of time and frequency resources,

wherein the at least one processor is further configured to select a time and frequency resource from the predetermined set of time and frequency resources, and

wherein sending the request comprises sending the request for random access using a selected time and frequency resource.

20. The apparatus of claim 15,

wherein the plurality of signal formats is for Orthogonal Frequency-Division Multiple Access (OFDMA) signals or Single-Carrier Frequency-Division Multiple Access (SC-FDMA) signals,

wherein the first time duration corresponds to a predetermined number of symbols, wherein a second time duration corresponds to a different number of symbols and

wherein a predetermined frequency bandwidth corresponds to a predetermined number of subcarriers.

21. The apparatus of claim 15, wherein the at least one processor is further configured to:

store the path loss at the device to facilitate a subsequent request for random access.

22. The apparatus of claim 15,

wherein the coding and modulation scheme corresponding to the first signal format of the plurality of signal formats and the coding and modulation scheme corresponding to a second signal format of the plurality of signal formats are different from each other.

23. The apparatus of claim 22,

wherein the signal format is selected such that a robustness of the coding and modulation scheme corresponding to the signal format selected by the device is commensurate with the path loss between the device and the base station.

24. The apparatus of claim 23, wherein the signal format is selected further such that, if the path loss is greater than a threshold value, the coding and modulation scheme corresponding to the signal format selected by the device is more robust than the coding and modulation scheme corresponding to the second signal format of the plurality of signal formats.

25. The apparatus of claim 14, further comprising storing the signal format selected by the device to facilitate a subsequent request for random access.

26. The apparatus of claim 14, wherein the request for random access is sent to facilitate sending of an Internet of Things (IoT) communication to the base station.

27. An apparatus for wireless communication of a device, comprising:

means for selecting, by the device, a signal format for a request for random access, wherein the signal format is selected from a plurality of signal formats based on a transmission-power capability of the device, a path loss between the device and a base station, or both, each of the plurality of signal formats corresponding to a respective coding and modulation scheme of a plurality of coding and modulation schemes such that the signal format selected by the device corresponds to a first coding and modulation scheme of the plurality of coding and modulation schemes, wherein each of the plurality of signal formats corresponds to a respective time duration, wherein the time duration of each signal format is based on the respective coding and modulation scheme; and

means for sending, by the device, the request for random access to the base station according to the selected signal format, wherein the request includes a known preamble common to the plurality of signal formats.

28. The apparatus of claim 27, further comprising:

means for determining the path loss between the apparatus and the base station, and wherein a first signal format for the request for random access is associated with a first time duration for transmission of the request for random access from the apparatus to the base station and wherein a second different signal format for the request for random access is associated with a second longer time duration for transmission of the request for random access from the apparatus to the base station.

29. The apparatus of claim 27, wherein the signal format is selected such that a robustness of the coding and modulation scheme corresponding to the signal format selected by the device is commensurate with the path loss between the apparatus and the base station, and wherein the signal format is selected further such that, if the path loss is less than a threshold value, the coding and modulation scheme corresponding to the signal format selected by the device is less robust than the coding and modulation scheme corresponding to a second signal format of the plurality of signal formats.

30. A non-transitory computer-readable medium storing computer executable code for wireless communication of a device, comprising code to:

select a signal format for a request for random access, wherein the signal format is selected from a plurality of signal formats based on a transmission-power capability of the device, a path loss between the device and a base station, or both, each of the plurality of signal formats corresponding to a respective coding and modulation scheme of a plurality of coding and modulation schemes such that the signal format selected by the device corresponds to a first coding and modulation scheme of the plurality of coding and modulation schemes, wherein each of the plurality of signal formats corresponds to a respective time duration, wherein the time duration of each signal format is based on the respective coding and modulation scheme; and

send the request for random access to the base station according to the signal format selected by the device, wherein the request includes a known preamble common to the plurality of signal formats.