Frame Structure and Data Mapping for License Assisted Access

• US 20160227545A1
• Filed: 01/29/2016
• Published: 08/04/2016
• Est. Priority Date: 01/30/2015
• Status: Active Grant

• Current Assignee: HFI Innovation, Inc. (MediaTek, Inc.)
• Original Assignee: MediaTek, Inc.
• Inventors: Yang, Weidong, Chen, Bo-Si, Liao, Pei-Kai, Li, Chien-Chang
• Granted Patent: US 10,397,795 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• 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 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management

Abstract

Methods and apparatus are provided for improved Licensed Assisted Access (LAA) networks. A LAA subframe is received via an unlicensed frequency band. Control information is communicated via predetermined symbol locations within the LAA subframe. An indication of a first and a second symbol locations is received. A LAA subframe is then received. It is determined if control information is present at the first or second symbol locations within the received LAA subframe. Demodulation parameters based on the control information are determined. The LAA subframe is demodulated using the demodulation parameters. An indication of a transmission duration is communicated to a UE. The transmission duration is determined based on the LAA subframe. A type of subframe is determined based on transmission duration. Automatic Gain Control (AGC) protection is provided in a LAA subframe. The AGC protection LLA subframe does not communicate control information in a symbol adjacent to a reservation signal.

Claims

1. A method, comprising:

(a) receiving an indication of a first symbol location and an indication of a second symbol location onto an User Equipment (UE);

(b) receiving a License Assisted Access (LAA) subframe, wherein the LAA subframe includes multiple symbols;

(c) determining if control information is present at the first symbol location within the received LAA subframe;

(d) determining if control information is present at the second symbol location within the received LAA subframe if it was determined in (c) that control information was not present at the first symbol location;

(e) determining demodulation parameters based on the control information that is present in either the first symbol location or the second symbol location; and

(f) demodulating the LAA subframe using the demodulation parameters.

2. The method of claim 1, wherein the LAA subframe is transmitted from a first base station to the UE via an unlicensed frequency band.

3. The method of claim 2, wherein the UE is also in communication with a second base station via a licensed frequency band.

4. The method of claim 1, wherein the LAA subframe is a truncated subframe.

5. The method of claim 1, wherein the first symbol location is symbol zero, and wherein the second symbol location is symbol seven.

6. The method of claim 1, wherein the control information includes at least one of:

a Cell-specific Reference Signal (CRS), a Physical Downlink Control Channel (PDCCH), a Physical Control Format Indicator Channel (PCFICH), or a Physical Broadcast Channel (PBCH).

7. The method of claim 3, wherein the UE communicates with the first base station using Long-Term Evolution (LTE) wireless communication, and wherein the UE communicates with the second base station using LTE wireless communication.

8. A method, comprising:

(a) receiving a License Assisted Access (LAA) subframe onto a User Equipment (UE), wherein the LAA subframe includes multiple symbols;

(b) determining a transmission duration based on the received subframe; and

(c) determining a type of subframe, wherein the determining is a function of the received LAA subframe and the transmission duration, wherein the LAA subframe was received via an unlicensed frequency band, and wherein steps (a) through (c) are performed by the UE.

9. The method of claim 8, wherein control information is included in the LAA subframe, and wherein the transmission duration is included in the channel information.

10. The method of claim 9, wherein the transmission duration is a total number of symbols in the received LAA subframe.

11. The method of claim 9, wherein the transmission duration is a number of remaining symbols in the received LAA subframe.

12. The method of claim 8, wherein the UE receives the LAA subframe from a first base station via an unlicensed frequency band, and wherein the UE is also in communication with a second base station via a licensed frequency band.

13. The method of claim 8, further comprising:

(d) determining the beginning of the LAA subframe when a reservation signal was not received.

14. The method of claim 8, further comprising:

(d) performing Physical Downlink Shared Channel (PDSCH) rate matching using the transmission duration.

15. The method of claim 8, further comprising:

(d) determining the Demodulation Reference Signal (DMRS) pattern using the transmission duration.

16. The method of claim 8, further comprising:

(d) determining if Channel State Information Reference Signal (CSI-RS) is transmitted in the LAA subframe, wherein the LAA subframe is a Time-Division Duplex (TDD) subframe.

17. A method, comprising:

(a) generating a License Assisted Access (LAA) subframe, wherein control information is included in the LAA subframe, and wherein a first symbol location where the control information is present is not adjacent to a second symbol location where the reservation signal is present; and

(b) transmitting the LAA subframe, wherein the transmitting of (b) is performed by a base station via an unlicensed frequency band.

18. The method of claim 17, wherein non-control information is present in a third symbol location that is adjacent to the second symbol location.

19. The method of claim 17, wherein the LAA subframe is transmitted using Long-Term Evolution (LTE) wireless communication.

20. The method of claim 17, wherein a User Equipment (UE) receives the LAA subframe and performs automatic gain control before receiving the channel information.