Method and wireless device for transmitting RACH preamble in wireless communication network

Patent metadata

Field	Value
Publication number	US-10798734-B2
Application number	US-201815938489-A
Country	US
Kind code	B2
Filing date	Mar 28, 2018
Priority date	Mar 28, 2017
Publication date	Oct 6, 2020
Grant date	Oct 6, 2020

Abstract

Embodiments herein provide a method and wireless device for transmitting a RACH preamble in a wireless communication network. The method includes steps of configuring a Narrowband Physical Random Access Channel (NPRACH) preamble comprising a first mini preamble and a second mini preamble; and transmitting the first mini preamble in a first available consecutive Up-Link (UL) sub-frames and the second mini preamble in a subsequent consecutive UL sub-frames reserved for UL transmission in at least one frame duration.

First claim

What is claimed is:

1. A method for transmitting a Physical Random Access Channel (PRACH) preamble in a wireless communication network, the method comprising:
dividing, by a wireless device, a Narrowband Physical Random Access Channel (NPRACH) preamble into a plurality of symbol groups;
selecting, by the wireless device, at least one first symbol group from the plurality of symbol groups and at least one second symbol group from the plurality of symbol groups;
adding, by the wireless device, a first Guard Period (GP) between the at least one first symbol group and the at least one second symbol group, wherein the first GP is added at the end of the at least one first symbol group;
adding, by the wireless device, a second GP at an end of the at least one second symbol group; and
transmitting, by the wireless device, the at least one first symbol group along with the first GP in first available consecutive Up-Link (UL) sub-frames; and
transmitting, by the wireless device, the at least one second symbol group along with the second GP in subsequent consecutive UL sub-frames after transmission of the at least one first symbol group along with the first GP, wherein the first available consecutive UL sub-frames and the subsequent consecutive UL sub-frames are reserved for UL transmission in at least one frame duration.

2. The method of claim 1 , wherein the frame is one of a Time Division Duplex (TDD) LTE frame and a Frequency Division Duplex (FDD) LTE frame.

3. The method of claim 1 , wherein a duration of the first GP and the second GP is determined by a cell radius.

4. The method of claim 1 , wherein the at least one first symbol group and the at least one second symbol group are hopped across frequency resources.

5. The method of claim 1 , wherein the at least one first symbol group and the at least one second symbol group comprises at least one symbol preceded by a Cyclic Prefix (CP).

6. The method of claim 5 , wherein a length of the CP in a first symbol group of the at least one first symbol group is one of shorter than and equal to a length of the CP in the remaining symbol groups of the same at least one first symbol group, and wherein a length of the CP in a first symbol group of the at least one second symbol group is one of shorter than and equal to a length of the CP in the remaining symbol groups of the same at least one second symbol group.

7. The method of claim 6 , wherein the length of CP is based on at least one of UL-DL configuration and special sub-frame configuration.

8. The method of claim 1 , wherein a number of symbols in the at least one first symbol group and the at least one second symbol group depends on a UL-DL configuration to be used for transmission of the NPRACH preamble.

9. The method of claim 8 , wherein the number of symbols in the at least one first symbol group and the at least one second symbol group is one of 2 and 3 when the UL-DL configuration is one of 1, 4, and 6.

10. The method of claim 8 , wherein the number of symbols in the at least one first symbol group and the at least one second symbol group is one of 4 and 5 when the UL-DL configuration is one of 0, 3, and 6.

11. The method of claim 8 , wherein the number of symbols in the at least one first symbol group and the at least one second symbol group is 1 when the UL-DL configuration is one of 2 and 5.

12. The method of claim 8 , wherein the number of symbols in the at least one first symbol group and the at least one second symbol group is one of same and different.

13. A wireless device for transmitting a Physical Random Access Channel (PRACH) preamble in a wireless communication network, the wireless device comprising:
a processor;
a memory;
a preamble configuration circuitry for:
dividing a Narrowband Physical Random Access Channel (NPRACH) preamble into a plurality of symbol groups,
selecting at least one first symbol group from the plurality of symbol groups and at least one second symbol group from the plurality of symbol groups,
adding a first Guard Period (GP) between the at least one first symbol group and the at least one second symbol group, wherein the first GP is added at the end of the at least one first symbol group,
adding a second GP at an end of the at least one second symbol group; and

a transceiver, coupled with the preamble configuration circuitry, configured for:
transmitting the at least one first symbol group along with the first GP in first available consecutive Up-Link (UL) sub-frames, and
transmitting, by the wireless device, the at least one second symbol group along with the second GP in subsequent consecutive UL sub-frames after transmission of the at least one first symbol group along with the first GP, wherein the first available consecutive UL sub-frames and the subsequent consecutive UL sub-frames are reserved for UL transmission in at least one frame duration.

14. The wireless device of claim 13 , wherein the frame is one of a Time Division Duplex (TDD) LTE frame and a Frequency Division Duplex (FDD) LTE frame.

15. The wireless device of claim 13 , wherein a duration of the first GP and the second GP is determined by a cell radius.

16. The wireless device of claim 13 , wherein the at least one first symbol group and the at least one second symbol group are hopped across frequency resources.

17. The wireless device of claim 13 , wherein the at least one first symbol group and the at least one second symbol group comprises at least one symbol preceded by a Cyclic Prefix (CP).

18. The wireless device of claim 17 , wherein a length of the CP in a first symbol group of the at least one first symbol group is one of shorter than and equal to a length of the CP in the remaining symbol groups of the same at least one first symbol group, and wherein a length of the CP in a first symbol group of the at least one second symbol group is one of shorter than and equal to a length of the CP in the remaining symbol groups of the same at least one second symbol group.

19. The wireless device of claim 17 , wherein the length of CP is based on at least one of UL-DL configuration and special sub-frame configuration.

20. The wireless device of claim 13 , wherein a number of symbols in the at least one first symbol group and the at least one second symbol group depends on a UL-DL configuration to be used for transmission of the NPRACH preamble.

21. The wireless device of claim 13 , wherein the number of symbols in the at least one symbol first group and the at least one second symbol group is one of 2 and 3 when the UL-DL configuration is one of 1, 4, and 6.

22. The wireless device of claim 13 , wherein the number of symbols in the at least one first symbol group and the at least one second symbol group is one of 4 and 5 when the UL-DL configuration is one of 0, 3, and 6.

23. The wireless device of claim 13 , wherein the number of symbols in the at least one first symbol group and the at least one second symbol group is 1 when the UL-DL configuration is one of 2 and 5.

24. The wireless device of claim 13 , wherein the number of symbols in the at least one first symbol group and the at least one second symbol group is one of same and different.

Assignees

• Centre Of Excellence In Wireless Tech
• Indian Inst Tech Madras
• Indian Institute Of Tech Madras

Inventors

• Reddy Budama Sree Charan Teja
• Milleth Jeniston Deviraj Klutto
• Kaimalettu Sunil
• Ramamurthi Bhaskar

Classifications

• H04W74/0833 Primary

  Random access procedures, e.g. with 4-step access · CPC title

• H04W74/004 Primary

  in the uplink, i.e. towards network · CPC title

• H04B1/713

  using frequency hopping · CPC title