Reference Signal Structure for OFDM Based Transmissions

• US 20130301538A1
• Filed: 05/01/2012
• Published: 11/14/2013
• Est. Priority Date: 09/21/2007
• Status: Abandoned Application

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Muharemovic, Tarik, Shen, Zukang
• Application Number:
  US13/461,772
• Publication Number:
  US 20130301538A1
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04J 13/0062 Zadoff-Chu
• CPC Class Codes: H04J 13/0066 GCL [generalized chirp-like] sequences
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA

Abstract

A method for transmitting a plurality of sequences across a plurality of bands of a wireless spectrum is described in which a first sequence Is produced using a set of reference signal sequences, wherein the set of reference signal sequences comprises at least CAZAC sequences and near-CAZAC sequences. A second sequence is also produced. The first sequence is transmitted in a first band of the wireless spectrum, and the second sequence is transmitted in a second band of the wireless spectrum. The first and the second sequences are transmitted concurrently by a same user equipment.

Claims

1-15. -15. (canceled)

16. An apparatus for transmitting a plurality of sequences across a plurality of bands of a wireless spectrum, comprising:

logic for producing a first sequence using a set of reference signal sequences;

logic for producing a second sequence; and

transmitter circuitry operable to transmit the first sequence in a first band of the wireless spectrum and to transmit the second sequence in a second band of the wireless spectrum.

17. The apparatus of claim 16, wherein the set of reference signal sequences comprises at least one of CAZAC sequences and near-CAZAC sequences,

wherein said CAZAC sequences comprise Zadoff-Chu (ZC) sequences, and

wherein said near-CAZAC sequences have a form exp(j*.pi.*.phi.(n)/4).

25. The apparatus of claim 16, wherein said transmitter circuitry is operable to transmit the first and the second sequences concurrently.

26. The apparatus of claim 16, wherein said logic for producing the first sequence comprises logic for modulation by a phase ramp.

27. The apparatus of claim 26, wherein said phase ramp parameters are indicated by received message.

28. The apparatus of claim 16, wherein said logic for producing a first sequence comprises a cyclic shift.

29. The apparatus of claim 17, wherein the length of .phi.(n) is an integral multiple of 12.

30. The apparatus of claim 16, wherein the second sequence is selected from a set of reference signal sequences.

31. The apparatus of claim 30, wherein said logic to produce a second sequence further comprises multiplication by at least one element of a cover sequence.

32. The apparatus of claim 31, wherein the cover sequence is selected from a group of cover sequences.

33. The apparatus of claim 32, wherein the cover sequence selection is indicated by a received message.

34. The apparatus of claim 31, wherein the cover sequence length equals the number of tone blocks allocated to the reference signal sequence.

18-24. -24. (canceled)

35. A method for transmitting a plurality of sequences across a plurality of bands of a wireless spectrum, comprising:

producing a first sequence using a set of reference signal sequences, wherein the set of reference signal sequences comprises at least CAZAC sequences and near-CAZAC sequences;

selecting a reference signal sequence from the set of reference signal sequences;

producing a second sequence using said set of reference signal sequences by multiplying each entry of the selected reference signal sequence by a covering element;

transmitting the first sequence in a first band of the wireless spectrum; and

transmitting the second sequence in a second band of the wireless spectrum, wherein the first and the second sequences are transmitted concurrently by a same user equipment.

36. A method for transmitting a plurality of sequences across a plurality of bands of a wireless spectrum, comprising:

producing a first sequence using a set of reference signal sequences, wherein the set of reference signal sequences comprises at least CAZAC sequences and near-CAZAC sequences;

producing a covering sequence comprising at least a second covering element; and

selecting a reference signal sequence from the set of reference signal sequences;

adding a phase ramping sequence to the phase component of the selected reference signal sequence;

producing a second sequence using said set of reference signal sequences including multiplying the second covering element with each entry of the selected reference signal sequence;

transmitting the first sequence in a first band of the wireless spectrum; and

transmitting the second sequence in a second band of the wireless spectrum, wherein the first and the second sequences are transmitted concurrently by a same user equipment.