METHODS, SYSTEMS AND APPARATUSES FOR OPERATION IN LONG-TERM EVOLUTION SYSTEMS

• US 20140086173A1
• Filed: 09/25/2013
• Published: 03/27/2014
• Est. Priority Date: 09/26/2012
• Status: Active Grant

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Inventors: Sadeghi, Pouriya, Tooher, J. Patrick, Stern-Berkowitz, Janet A., Lee, Moon-il, Pelletier, Ghyslain, Tamaki, Nobuyuki, Nayeb Nazar, Shahrokh, Sun, Li-Hsiang
• Granted Patent: US 9,553,701 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 27/261 Details of reference signals
• CPC Class Codes: H04L 27/2649 Demodulators
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/003 Arrangements for allocating sub-channels of the transmission path
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 5/0092 Indication of how the channel is divided
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04W 68/02 Arrangements for increasing efficiency of notification or paging channel
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/30 Resource management for broadcast services
• CPC Class Codes: H04W 72/51 based on terminal or device properties

Abstract

Methods, systems and apparatuses for operation in long-term evolution (LTE) systems are provided, including a method implemented by a wireless transmit/receive unit (WTRU) served by a cell, where an enhanced physical broadcast channel (ePBCH) may be sent by the cell and may including basic information for WTRU control. The method may include receiving, by the WTRU, the ePBCH, and demodulating the ePBCH based on a demodulation reference signal (DMRS). In some embodiments, demodulating the ePBCH may be based on any of: a primary synchronization signal (PSS), a secondary synchronization signal; and a cell-specific reference signal (CRS), as well. Also provided is a method implemented by a WTRU in a vicinity of a dormant cell. The method may include any of: receiving, from a dormant cell, a signal; receiving, from a serving cell, a trigger to initiate measurement of one or more dormant cells; and measuring the signal.

Claims

7. A method implemented by a network resource to configure one or more WTRUs that are within a coverage area of a cell associated with the network resource, the method comprising:

transmitting, by the network resource, a first set of ePBCH-related information on a first DMRS port; and

transmitting, by the network resource, a second set of ePBCH-related information on a second DMRS port.

8. The method of claim 7, wherein the first set of ePBCH-related information on the first DMRS port includes a first set of attributes associated with a first type of WTRU and the second set of ePBCH-related information on the second DMRS port includes a second set of attributes associated with a second, different type of WTRU.

9. The method of claim 7, wherein the first set of ePBCH-related information supports a bandwidth which is wider than a bandwidth supported by the second set of ePBCH-related information.

10. A method implemented by a WTRU, the method comprising:

receiving, by the WTRU from a network resource, first and second sets of ePBCH-related information on first and second DMRS ports, respectively;

decoding, by the WTRU, the first and second sets of ePBCH-related information;

selecting, by the WTRU, one of the first or second sets of ePBCH-related information; and

configuring the WTRU for operation in accordance with the selected one of the first or second sets of ePBCH-related information.

11. The method of claim 10, wherein, if the WTRU is of a first type, the selecting of the first or second sets of ePBCH-related information includes selecting the first set of ePBCH-related information and, if the WTRU is of a second type, the selecting of the first or second sets of ePBCH-related information includes selecting the second set of ePBCH-related information.

12. The method of claim 11, wherein the WTRU of the first type includes a WTRU having a first bandwidth capability and the WTRU of the second type includes a WTRU having a second, higher bandwidth capability.

13. A method implemented by a network resource to configure one or more WTRUs within overlapping coverage areas of a plurality of cells associated with the network resource, wherein the plurality of cells have overlapping resource blocks (RBs), the method comprising:

generating, for first and second cells of the plurality of cells, first and second ePBCH-related information, wherein the first and second ePBCH-related information have a set of synchronization signals in common; and

transmitting, by the network resource, the first and second ePBCH-related information in the overlapping RBs.

14. The method of claim 13, wherein the first and second ePBCH-related information are transmitted in respective first and second subsets of resource elements in the overlapping RBs.

15. The method of claim 13, wherein the set of synchronization signals comprise any of a set of primary synchronization signals and secondary synchronization signals.

16. The method of claim 13, wherein the first and second ePBCH-related information are transmitted on respective first and second DMRS ports.

17. The method of claim 13, wherein the first and second cells have respective first and second transmission bandwidths, and wherein the first transmission bandwidth encompasses the second transmission bandwidth in whole or in part.

18. The method of claim 13, wherein the overlapping coverage areas of the plurality of cells comprises:

a first coverage area of the first cell and a second coverage area of the second cell, and wherein the first and second coverage areas partially overlap.

19. A method implemented by a WTRU within overlapping coverage areas of a plurality of cells associated with the network resource, wherein first and second cells of the plurality of cells have overlapping resource blocks (RBs), the method comprising:

receiving a set of synchronization signals from any of first and second ePBCH-related information of first and second cells received in the overlapping RBs, wherein the set of synchronization signals is common to both of the first and second ePBCH-related information; and

determining a cell identifier of the first cell based, at least in part, on the set of synchronization signals.

1. A method implemented by a wireless transmit/receive unit (WTRU) served by a cell, an enhanced physical broadcast channel (ePBCH) sent by the cell including basic information for WTRU control, the method comprising:

receiving, by the WTRU, the ePBCH; and

demodulating, by the WTRU, the ePBCH based on a demodulation reference signal (DMRS).

2. The method of claim 1, wherein the demodulating is further based on any of:

(1) a primary synchronization signal (PSS);

(2) a secondary synchronization signal (SSS); and

/or (3) a cell-specific reference signal (CRS).

3. The method of claim 1, wherein the demodulating of the ePBCH is based on a single or multiple DMRS, the method further comprising:

determining, by the WTRU, a DMRS port for the ePBCH demodulation according to one of;

(1) a predefined and/or pre-configured DMRS port;

or (2) a function of a cell ID, a PSS index and/or an SSS index; and

(3) a blind detection of the DMRS port out of a predefined set of DMRS ports.

4. The method of claim 1, wherein the demodulating of the ePBCH is based on a plurality of DMRS ports, the method further comprising:

selecting, by the WTRU, one of the plurality of DMRS ports;

associating available sets of resource elements to the selected one of the DMRS ports; and

demodulating the ePBCH in the resource elements associated with the selected one of the DMRS ports using the selected one of the DMRS ports.

5. The method of claim 1, further comprising:

receiving, by the WTRU, the ePBCH in one or more resource blocks (RBs) of a plurality of subframes;

determining, by the WTRU, at least a portion of system frame numbers (SFNs) based on;

(1) subframe locations of the ePBCH;

(2) locations of the RBs that carry the ePBCH;

(3) scrambling used for ePBCH contexts; and

/or (4) cyclic redundancy checks (CRCs).

6. The method of claim 1, wherein the ePBCH is mapped to one or more resource blocks at any of:

(1) a predefined subframe or predefined subframes within a radio frame, (2) a subframe or subframes where positions in the radio frame are a function of cell ID;

(3) a subframe or subframes where the positions in the radio frame are a function of a mode of operation;

or (4) a subframe or subframes where the positions in the radio frame are a function of frame number or system frame number (SFN)

20. The method of claim 19, further comprising:

determining a cell identifier of the second cell based, at least in part, on the determined cell identifier of the first cell.

21. The method of claim 19, further comprising:

determining a cell identifier of the second cell based on one or more factors, including any of first and second ePBCH-related information.

22. The method of claim 19, further comprising:

receiving one or both of the first and second ePBCH-related information.

23. The method of claim 19, wherein the first and second ePBCH-related information are received in respective first and second subsets of resource elements in the overlapping RBs.

24. The method of claim 19, wherein the set of synchronization signals comprise any of a set of primary synchronization signals and secondary synchronization signals.

25. The method of claim 19, wherein the first and second ePBCH-related information are received on respective first and second DMRS ports.

25-1. The method of claim 19, wherein the first and second cells have respective first and second transmission bandwidths.

26. A method implemented by a wireless transmit/receive unit (WTRU) in a vicinity of a dormant cell, the method comprising:

receiving, by the WTRU from a dormant cell, a signal;

receiving, by the WTRU from a serving cell, a trigger to initiate measurement of one or more dormant cells; and

measuring, by the WTRU, the signal.

27. The method of claim 26, wherein:

the signal is an aperiodic signal or a one-time signal; and

the measuring of the signal includes measuring timing of the aperiodic signal, a band of the aperiodic signal;

a sequence used for the aperiodic signal and/or an orthogonal cover code.

28. The method of claim 26, further comprising:

receiving, by the WTRU, a bit field indicating to the WTRU a set of resources to be used for a subsequent measurement report.

29. The method of claim 26, further comprising:

determining, by the WTRU, whether the signal satisfies one or more criteria;

sending, by the WTRU to a serving cell, a measurement report when the one or more criteria are satisfied.

30. The method of claim 29, wherein the measurement report include an indicator for indicating whether the WTRU is able to detect the signal in the configured resources.

31. A method implemented by an access point for a dormant cell, the method comprising:

establishing one or more aperiodic signal configurations for the dormant cell;

configuring, by the dormant cell, resources to be used for communicating a dormant-state aperiodic signal of the dormant cell;

inform, by the dormant cell, one or more neighboring cells, cell clusters and/or a macro cell of the configured resources to be used for communicating the dormant-state aperiodic signal;

receiving, by the dormant cell, a request to trigger the dormant-state aperiodic signal; and

sending, by the dormant cell in response to the received request, the dormant-state aperiodic signal using the configured resources.

32. The method of claim 31, wherein the receiving of the request to trigger the dormant-state aperiodic signal includes receiving, from a neighboring cell via an X2 interface, the request to trigger the dormant-state aperiodic signal.

33. The method of claim 32, wherein the request to trigger the dormant-state aperiodic signal includes the neighboring cells desired aperiodic signaling configuration, the method further comprising sending, by the dormant cell, an acknowledgement signal via the X2 interface to the neighboring cell indicating that the dormant cell is to use the desired aperiodic signaling configuration.

34. The method of claim 31, wherein the receiving of the request to trigger the dormant-state aperiodic signal includes receiving, from a wireless transmit/receive unit (WTRU) via a physical random access channel (PRACH) transmission, the request to trigger the dormant-state aperiodic signal.

35. A method implemented by a wireless transmit/receive unit (WTRU), the method comprising:

monitoring, by the WTRU, for one or more dormant-state signals;

measuring, by the WTRU, at least one criteria of each dormant-state signal;

comparing, for each dormant-state signal, the at least one criteria to a threshold, as a comparison result;

determining, by the WTRU, whether to send a measurement report based on the comparison results; and

sending, by the WTRU, the measurement report.

36. The method of claim 35, wherein the one or more dormant-state signals are aperiodic signals, the method further comprising initiating, by the WTRU, a physical random access channel (PRACH) transmission, as a request to trigger the one or more dormant-state signals from dormant cells in a vicinity of the WTRU.

37. The method of claim 35, wherein the monitoring for the one or more dormant-state signals includes:

blindly searching for the one or more dormant-state signals; and

detecting the one or more dormant state signals based on the blind search.

38. The method of claim 35, wherein the measuring of the at least one criteria of each dormant-state signal includes determine any of:

(1) a subframe location of the dormant-state signal;

(2) time location of the dormant-state signal; and

/or (3) a band of the dormant-state signal, the subframe location, time location and band being functions of subframe resources or physical random access channel (PRACH) resources used for a PRACH trigger transmission.