Coverage extension level for coverage limited device

• US 10,419,947 B2
• Filed: 12/14/2017
• Issued: 09/17/2019
• Est. Priority Date: 08/08/2013
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Intel IP Corporation (Intel Corporation)
• Inventors: Xiong, Gang, Fwu, Jong-Kae
• Primary Examiner(s): Mesfin, Yemane
• Assistant Examiner(s): Baron, Henry
• Application Number:
  US15/842,528
• Publication Number:
  US 20180184306A1
• Time in Patent Office: 642 Days
• CPC Class Codes: E04G 23/0218 Increasing or restoring the load-bearing capacity of building construction elements E04G23/0203 and E04G23/0266 take precedence
• CPC Class Codes: E04H 9/025 Structures with concrete columns
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04B 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 5/0012 Hopping in multicarrier systems for frequency hopping in spread spectrum systems H04B1/713
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0058 Allocation criteria
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04L 5/1469 using time-sharing
• CPC Class Codes: H04W 16/26 Cell enhancers or enhancement, e.g. for tunnels, building shadow
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/14 : Reselecting a network or an air interface
• CPC Class Codes: H04W 36/28 : involving a plurality of connections, e.g. multi-call or multi-bearer connections
• CPC Class Codes: H04W 36/32 : by location or mobility data, e.g. speed data
• CPC Class Codes: H04W 4/023 : using mutual or relative location information between multiple location based services [LBS] targets or of distance thresholds
• CPC Class Codes: H04W 4/70 : Services for machine-to-machine communication [M2M] or machine type communication [MTC]
• CPC Class Codes: H04W 48/12 : using downlink control channel
• CPC Class Codes: H04W 48/16 : Discovering, processing access restriction or access information
• CPC Class Codes: H04W 52/0206 : in access points, e.g. base stations access point devices per se H04W88/08
• CPC Class Codes: H04W 52/0209 : in terminal devices terminal devices per se H04W88/02
• CPC Class Codes: H04W 52/0219 : where the power saving management affects multiple terminals
• CPC Class Codes: H04W 56/0005 : synchronizing of arrival of multiple uplinks
• CPC Class Codes: H04W 64/006 : with additional information processing, e.g. for direction or speed determination
• CPC Class Codes: H04W 72/0446 : Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/20 : Control channels or signalling for resource management
• CPC Class Codes: H04W 72/541 : using the level of interference
• CPC Class Codes: H04W 74/0833 : Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 76/10 : Connection setup
• CPC Class Codes: H04W 76/14 : Direct-mode setup
• CPC Class Codes: H04W 76/27 : Transitions between radio resource control [RRC] states
• CPC Class Codes: H04W 8/02 : Processing of mobility data, e.g. registration information at HLR [Home Location Register] or VLR [Visitor Location Register]; Transfer of mobility data, e.g. between HLR, VLR or external networks
• CPC Class Codes: H04W 88/02 : Terminal devices
• CPC Class Codes: H04W 88/04 : adapted for relaying to or from another terminal or user
• CPC Class Codes: H04W 88/08 : Access point devices
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

Generally discussed herein are systems, apparatuses, and methods that can provide a coverage enhancement to a coverage limited device. According to an example a method can include determining a received signal strength of a reference signal transmitted from a base station, determining a coverage enhancement based on the determined signal strength, or transmitting a signature sequence of a plurality of signature sequences a first repeated number of times corresponding to the determined coverage enhancement.

Claims

1. An apparatus of a user equipment (UE), the apparatus comprising:

a memory configured to store physical random access channel (PRACH) configuration information for coverage enhancement; and

processing circuitry, configured to;

decode system information that includes the PRACH configuration information, the PRACH configuration information comprising signal thresholds for coverage enhancement levels and PRACH resource sets for the coverage enhancement levels;

determine a coverage enhancement level based on a measured signal level and the signal thresholds from among the coverage enhancement levels of the PRACH configuration information stored in the memory;

determine whether PRACH frequency hopping is enabled;

select PRACH characteristics based on the coverage enhancement level, the PRACH characteristics comprising a number of PRACH repetitions, one of a group of preamble sequences, and a PRACH resource from one of the PRACH resource sets; and

initiate a random access procedure that comprises transmission of the preamble sequence using the number of repetitions on the PRACH resource, at least one of the PRACH characteristics further dependent on whether the PRACH frequency hopping is enabled.

2. The apparatus of claim 1, wherein the at least one of the PRACH characteristics comprises the PRACH resource.

3. The apparatus of claim 2, wherein different PRACH resources are selected when the PRACH frequency hopping is enabled.

4. The apparatus of claim 3, wherein the PRACH resource selected is different for each repetition of the preamble sequence when the PRACH frequency hopping is enabled.

5. The apparatus of claim 1, wherein the PRACH configuration information indicates which of the PRACH resource sets are associated with each of the enhanced coverage levels.

6. The apparatus of claim 5 wherein the PRACH configuration is configured by higher level layers based on the PRACH configuration information.

7. The apparatus of claim 1 wherein the processing circuity is configured to:

determine if the UE is in enhanced coverage based on the measured signal level;

select the coverage enhancement level if the UE is determined to be in enhanced coverage, and

refrain from selection of a coverage enhancement level if the UE is not determined to be in enhanced coverage.

8. The apparatus of claim 2 wherein each of the enhanced coverage levels is associated with one of the PRACH resource sets.

9. The apparatus of claim 1 wherein the UE is an internet-of-things (IoT) communication device configured for machine-type communication.

10. The apparatus of claim 1 wherein the processing circuitry is further configured to select a transmit power level based on the coverage enhancement level, the transmit power level inversely related to the coverage enhancement level.

11. The apparatus of claim 1 wherein the processing circuitry is further configured to select a transmit power level based on the number of repetitions, the transmit power level inversely related to the number of repetitions.

12. The apparatus of claim 1, wherein:

selection the coverage enhancement level is dependent on whether the coverage enhancement level selected is supported by an evolved Node B (eNB) serving the UE, and

when the coverage enhancement level selected is unsupported by the eNB, the processing circuitry is configured to select a PRACH repetition level of a closest coverage enhancement level supported by the eNB regardless of a relative position of the coverage enhancement level selected to the coverage enhancement level supported.

13. The apparatus of claim 12, wherein the processing circuitry is further configured to:

in response to a determination that the PRACH repetition level does not provide reliable communication, switch to a next greatest PRACH repetition level supported by the eNB.

14. The apparatus of claim 1, wherein:

selection the coverage enhancement level is dependent on whether the coverage enhancement level selected is supported by an evolved Node B (eNB) serving the UE, and

when an initial coverage enhancement level selected is unsupported by the eNB, the processing circuitry is configured to select the coverage enhancement level to be a coverage enhancement level supported by the eNB that is greater than the initial coverage enhancement level selected.

15. A non-transitory computer-readable storage medium that stores instructions for execution by processing circuitry of user equipment (UE) to configure the UE to perform operations to:

select a coverage enhancement level based on a measured reference signal level and predetermined signal thresholds;

determine a physical random access channel (PRACH) configuration and a number of PRACH repetitions based on the selected coverage enhancement level;

select a PRACH resource from one of a plurality of PRACH resource sets that corresponds to the selected coverage enhancement level; and

initiate a random access procedure in accordance with the PRACH configuration, the random access procedure comprising transmission of a selected preamble sequence in accordance with the number of repetitions on the selected PRACH resource, the PRACH resource further dependent on a transmission condition of the transmission of the selected preamble sequence, the PRACH resource used for transmission of the selected preamble sequence configured to vary between at least some of the repetitions of the selected preamble sequence when the transmission condition is met.

16. The non-transitory computer-readable storage medium of claim 15, wherein the processing circuitry is configured to decode system information that includes PRACH configuration information for coverage enhancement, the PRACH configuration information including the power thresholds for coverage enhancement levels,

wherein the PRACH resource sets are associated with the coverage enhancement levels,

wherein the PRACH configuration information indicates which of the PRACH resource sets are associated with each of the enhanced coverage levels.

17. The non-transitory computer-readable storage medium of claim 16 wherein each of the enhanced coverage levels is associated with one of the PRACH resource sets.

18. The non-transitory computer-readable storage medium of claim 15, wherein the processing circuitry is configured to select a preamble sequence from a group of preamble sequences, the group corresponding to the selected coverage enhancement level.

19. The non-transitory computer-readable storage medium of claim 15, wherein the transmission condition is PRACH frequency hopping.

20. The non-transitory computer-readable storage medium of claim 15, wherein the PRACH resource used for transmission of the selected preamble sequence varies between each repetition of the selected preamble sequence.

21. An apparatus of a user equipment (UE), the apparatus comprising:

a memory; and

processing circuitry, configured to;

decode system information that includes physical random access channel (PRACH) configuration information for coverage enhancement, the PRACH configuration information including power thresholds for coverage enhancement levels and PRACH resource sets for the coverage enhancement levels;

select a coverage enhancement level based on a measured power level and the power thresholds;

based on the coverage enhancement level, select;

a number of PRACH repetitions,

a preamble sequence, and

a PRACH resource; and

initiate a random access procedure in accordance with the PRACH configuration, the random access procedure comprising transmission of the preamble sequence in accordance with the number of repetitions on the selected PRACH resource, the PRACH resource further dependent on a transmission condition of the transmission of the preamble sequence, the PRACH resource used for transmission of the preamble sequence configured to vary between at least some of the repetitions on the PRACH resource when the transmission condition is met.

22. The apparatus of claim 21 wherein:

each of the enhanced coverage levels is associated with one of the PRACH resource sets, and

the processing circuitry is configured to select a preamble sequence from a group of preamble sequences, the group corresponding to the selected coverage enhancement level.

23. The apparatus of claim 21, wherein the transmission condition is PRACH frequency hopping.

24. The apparatus of claim 21, wherein the PRACH resource used for transmission of the selected preamble sequence varies between each repetition of the selected preamble sequence.