ENABLING TECHNOLOGIES FOR LTE ON UNLICENSED SPECTRUM

• US 20170265083A1
• Filed: 02/01/2017
• Published: 09/14/2017
• Est. Priority Date: 03/14/2016
• Status: Active Application

• Current Assignee: NEC Corporation
• Original Assignee: NEC Laboratories America Inc (NEC Corporation)
• Inventors: Khojastepour, Mohammad, Chai, Eugene, Sundaresan, Karthikeyan, Rangarajan, Sampath
• Granted Patent: US 10,292,054 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 28/26 Resource reservation
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 74/006 in the downlink, i.e. towards the terminal
• CPC Class Codes: H04W 74/0816 with collision avoidance
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/10 adapted for operation in multiple networks, e.g. multi-mode access points

Abstract

Methods and a system are provided for enabling coexistence of WIFI and Long Term Evolution (LTE) in a wireless communication system. A method includes embedding in a data sequence, by a base station capable of transmitting and receiving LTE frames, a channel reservation packet that (i) is detectable by a WIFI receiver and (ii) reserves a particular one of a plurality of available unlicensed communication channels for a transmission duration of the data sequence. The method further includes transmitting, by the base station, the data sequence including the embedded channel reservation packet.

Claims

1. A method for enabling coexistence of WIFI and Long Term Evolution (LTE) in a wireless communication system, the method comprising:

embedding in a data sequence, by a base station capable of transmitting and receiving LTE frames, a channel reservation packet that (i) is detectable by a WIFI receiver and (ii) reserves a particular one of a plurality of available unlicensed communication channels for a transmission duration of the data sequence; and

transmitting, by the base station, the data sequence including the embedded channel reservation packet.

2. The method of claim 1, wherein said embedding step embeds a WIFI CTS signal into the channel reservation packet.

3. The method of claim 2, wherein the WIFI CTS signal is embedded into the channel reservation packet by determining a frequency domain equivalent of the WIFI CTS signal and embedding the frequency domain equivalent as data in the channel reservation packet.

4. The method of claim 2, wherein the frequency domain equivalent is embedded as data in an Orthogonal Frequency-Division Multiple Access frame of the channel reservation packet.

5. The method of claim 1, wherein the, data sequence is transmitted by the base station using a Physical Downlink Shared Channel.

6. The method of claim 1, wherein the data sequence is transmitted as a single Orthogonal Frequency-Division Multiple Access (OFDMA) tone capable of regenerating a WIFI detectable signal by the WIFI receiver.

7. The method of claim 6, wherein the single OFDMA tone consists of only systematic bits of a coded sequence.

8. The method of claim 6 wherein the single OFDMA tone is partitioned into different partitions, and wherein different ones of the different partitions are assigned to different virtual LTE users.

9. The method of claim 1, wherein a highest available modulation rate is used to transmit the data sequence including the embedded channel reservation packet.

10. A non-transitory article of manufacture tangibly embodying a computer readable program which when executed causes a computer to perform the steps of claim 1.

11. A system for enabling coexistence of WIFI and Long Term Evolution (LTE) in a wireless communication system, the system comprising:

a base station, capable of transmitting and receiving LTE frames, and configured to;

embed, in a data sequence, a reservation packet that (i) is detectable by a WIFI receiver and (ii) reserves a particular one of a plurality of available unlicensed communication channels for a transmission duration of the data sequence; and

transmit the data sequence including the embedded reservation packet.

12. The system of claim 11, wherein said base station embeds a WIFI CTS signal into the reservation packet.

13. The system of claim 12, wherein the base station embeds the WIFI CTS signal into the reservation packet by determining a frequency domain equivalent of the WIFI CTS signal and embedding the frequency domain equivalent as data in the reservation packet.

14. A method for enabling coexistence of WIFI and Long Term Evolution (LTE) in a wireless communication system, the method comprising:

sensing, by a base station capable of transmitting and receiving LTE frames, WIFI signals in each of a plurality of frequency bands, the plurality of frequency bands corresponding to a plurality of unlicensed communication channels;

choosing, by the base station, only one of the plurality of frequency bands for a LTE transmission; and

performing, by the base station, LTE transmissions in other ones of the plurality of frequency bands without WIFI sensing.

15. The method of claim 14, wherein a WIFI interface assignment and a LTE traffic allocation are made jointly to all of the plurality of unlicensed communication channels.

16. The method of claim 14, wherein said sensing step comprises periodically deploying a single WIFI interface on each of the plurality of unlicensed communication channels to sense the WIFI signals.

17. The method of claim 14, wherein said sensing step comprises periodically deploying a single WIFI interface on each of the plurality of unlicensed communication channels to estimate a potential impact of an absence of WIFI carrier sensing on the each of the plurality of unlicensed communication channels.

18. The method of claim 17, further comprising solving a joint optimization problem based on the estimated potential impact, the joint optimization problem for jointly performing a WIFI interface assignment and a LTE traffic allocation.

19. The method of claim 14, wherein the joint optimization problem determines which of the plurality of unlicensed communication channels to perform a WIFI interface channel sensing feature on that minimizes an impact of an absence of performing carrier sensing on other ones of the plurality of unlicensed communication channels.

20. A non-transitory article of manufacture tangibly embodying a computer readable program which when executed causes a computer to perform the steps of claim 14.