Sharing channels in a licensed-assisted access in long term evolution operation

• US 9,565,568 B2
• Filed: 11/14/2014
• Issued: 02/07/2017
• Est. Priority Date: 11/14/2014
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Suzuki, Takashi, Vutukuri, Eswar, Anderson, Nicholas William, Smadi, Mohammed Nawaf, Hole, David Philip, Barrett, Stephen John
• Primary Examiner(s): LAM, YEE F
• Application Number:
  US14/542,414
• Publication Number:
  US 20160142920A1
• Time in Patent Office: 816 Days
• US Class Current: 1/1
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/1215 for collaboration of different radio technologies
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 74/0808 using carrier sensing, e.g. carrier sense multiple access [CSMA]
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A channel sharing method includes determining a starting time for transmission on an LAA-LTE channel. A length of a hybrid preamble is determined based on the starting time and a predetermined transmission time boundary. Subsequent to determining the length of the hybrid preamble, the hybrid preamble having the determined length is transmitted. Subsequent to the hybrid preamble, a Long Term Evolution (LTE) signal is transmitted.

Claims

1. A method for transmitting on a Licensed-Assisted Access in Long Term Evolution (LAA-LTE) channel, comprising:

determining a starting time for transmission on the LAA-LTE channel;

determining a length of a hybrid preamble based on the starting time and based on a predetermined transmission time boundary;

transmitting, subsequent to determining the length of the hybrid preamble, the hybrid preamble having the determined length, wherein the hybrid preamble is transmitted in a first subframe that is prior to the predetermined transmission time boundary;

transmitting, subsequent to transmission of the hybrid preamble, a Long Term Evolution (LTE) signal, wherein the LTE signal is transmitted in a second subframe different than the first subframe, the second subframe being after the predetermined transmission time boundary;

receiving or transmitting a grant regarding a second LTE signal, wherein the grant includes an indication to configure the second LTE signal without a preceding hybrid preamble;

in response to the indication, receiving or transmitting the second LTE signal without a preceding hybrid preamble; and

wherein the first subframe comprises a second LTE signal that occupies a subset of fewer than all orthogonal frequency-division multiplexing (OFDM) symbols in the first subframe, and wherein the hybrid preamble is transmitted during a time period corresponding to OFDM symbols not within the subset.

2. The method of claim 1, wherein the predetermined transmission time boundary is a Transmission Time Interval (TTI) boundary.

3. The method of claim 1, wherein the hybrid preamble comprises a Wireless Local Area Network (WLAN) Compatible Section (WCS) that indicates a length of the LTE signal.

4. The method of claim 3, wherein the length of the hybrid preamble is equal to a duration of the Wireless Local Area Network (WLAN) Compatible Section (WCS).

5. The method of claim 1, wherein the hybrid preamble comprises a Wireless Local Area Network (WLAN) Compatible Section (WCS) and a Variable Length Section (VLS), and the WCS indicates a length of the LTE signal and the VLS has a length that is determined based on a difference between the length of the hybrid preamble and a length of the WCS.

6. The method of claim 5 wherein the length of the hybrid preamble is larger than the length of the WCS.

7. The method of claim 1, wherein the hybrid preamble comprises a Variable Length Section (VLS) having a length that is determined based on the length of the hybrid preamble.

8. The method of claim 1, further comprising:

receiving, prior to transmitting the hybrid preamble, a transmission grant that grants a transmission of the LTE signal and an indication that indicates a transmission power level of the hybrid preamble; and

transmitting, in response to the transmission grant, the hybrid preamble in accordance with the indication.

9. The method of claim 8, wherein the indication indicates that the hybrid preamble is transmitted at a normal power level or at a reduced power level.

10. The method of claim 1, wherein the LAA-LTE channel is an unlicensed carrier that is configured for a Licensed-Assisted operation.

11. The method of claim 1, wherein the hybrid preamble is transmitted by a User Equipment (UE).

12. The method of claim 1, wherein the hybrid preamble is transmitted by an evolved Node B (eNB).

13. A user equipment (UE), comprising:

a memory; and

at least one hardware processor communicatively coupled with the memory and configured to;

determine a starting time for transmission on a Licensed-Assisted Access in Long Term Evolution (LAA-LTE) channel;

determine a length of a hybrid preamble based on the starting time and based on a predetermined transmission time boundary;

transmit, subsequent to determining the length of the hybrid preamble, the hybrid preamble having the determined length, wherein the hybrid preamble is transmitted in a first subframe that is prior to the predetermined transmission time boundary; and

transmit, subsequent to transmission of the hybrid preamble, a Long Term Evolution (LTE) signal, wherein the LTE signal is transmitted in a second subframe different than the first subframe, the second subframe being after the predetermined transmission time boundary;

receive or transmit a grant regarding a second LTE signal, wherein the grant includes an indication to configure the second LTE signal without a preceding hybrid preamble;

in response to the indication, receive or transmit the second LTE signal without a preceding hybrid preamble; and

wherein the first subframe comprises a second LTE signal that occupies a subset of fewer than all orthogonal frequency-division multiplexing (OFDM) symbols in the first subframe, and wherein the hybrid preamble is transmitted during a time period corresponding to OFDM symbols not within the subset.

14. The UE of claim 13, wherein the predetermined transmission time boundary is a Transmission Time Interval (TTI) boundary.

15. The UE of claim 13, wherein the hybrid preamble comprises a Wireless Local Area Network (WLAN) Compatible Section (WCS) that indicates a length of the LTE signal.

16. The UE of claim 15, wherein the length of the hybrid preamble is equal to a duration of the Wireless Local Area Network (WLAN) Compatible Section (WCS).

17. A base station, comprising:

a memory; and

at least one hardware processor communicatively coupled with the memory and configured to;

determine a starting time for transmission on a Licensed-Assisted Access in Long Term Evolution (LAA-LTE) channel;

determine a length of a hybrid preamble based on the starting time and based on a predetermined transmission time boundary;

transmit, subsequent to determining the length of the hybrid preamble, the hybrid preamble having the determined length, wherein the hybrid preamble is transmitted in a first subframe that is prior to the predetermined transmission time boundary;

transmit, subsequent to transmission of the hybrid preamble, a Long Term Evolution (LTE) signal, wherein the LTE signal is transmitted in a second subframe different than the first subframe, the second subframe being after the predetermined transmission time boundary;

transmit, to a user equipment (UE), a transmission grant that grants a transmission of a second LTE signal, wherein the transmission grant includes an indication to transmit the second LTE signal without a preceding hybrid preamble; and

in response to the indication, receiving, from the UE, the second LTE signal without a preceding hybrid preamble;

wherein the first subframe comprises a second LTE signal that occupies a subset of fewer than all orthogonal frequency-division multiplexing (OFDM) symbols in the first subframe, and wherein the hybrid preamble is transmitted during a time period corresponding to OFDM symbols not within the subset.