Methods and apparatus for subframe configuration and generation in a multi-carrier communication system

• US 9,198,179 B2
• Filed: 05/13/2014
• Issued: 11/24/2015
• Est. Priority Date: 01/29/2004
• Status: Active Grant

• Current Assignee: Guangdong OPPO Mobile Telecommunications Corporation Limited
• Original Assignee: Neocific Incorporated
• Inventors: Li, Xiaodong, Lo, Titus, Li, Kemin, Huang, Haiming
• Primary Examiner(s): Rinehart, Mark
• Assistant Examiner(s): HOPKINS, MATTHEW A
• Application Number:
  US14/276,736
• Publication Number:
  US 20140247805A1
• Time in Patent Office: 560 Days
• Field of Search: 370/344, 370/203.1
• US Class Current: 1/1
• CPC Class Codes: H04B 7/2656 for structure of frame, burst
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/1819 with retransmission of additional or different redundancy
• CPC Class Codes: H04L 27/2627 Modulators
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04L 5/1484 operating bytewise
• CPC Class Codes: H04W 72/044 based on the type of the allocated resource
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 72/30 Resource management for broadcast services

Abstract

Methods and apparatus for subframe configuration and generation in a multi-cell multi-carrier system. A frame for radio transmission in the system consists of multiple subframes, and each subframe consists of multiple Orthogonal Frequency Division Multiplexing (OFDM) symbols. Training symbols, frequency-domain data scrambling, size of Fast-Fourier Transform (FFT), or length of cyclic prefix can be configured differently for each subframe to facilitate different applications, such as unicasting or broadcasting.

Claims

1. A method for a base station in a cell of a multi-cell wireless system using a transmission frame structure, each frame comprising a plurality of subframes, each subframe comprising a plurality of time slots, each time slot comprising a plurality of orthogonal frequency division multiplexing (OFDM) symbols, the method comprising:

broadcasting a control signal containing a cell identity associated with the cell of the base station;

forming a subchannel by selecting a plurality of OFDM subcarriers within a frequency channel in a time slot; and

transmitting data over the subchannel to a mobile station in the cell, wherein;

the data are scrambled based on the cell identity;

the scrambled data are modulated to produce modulated data symbols; and

the modulated data symbols are mapped, based on the cell identity, to the plurality of OFDM subcarriers in the subchannel.

2. The method of claim 1, wherein a subframe containing the time slot is characterized by a specific type of transmission.

3. The method of claim 2, wherein characteristics of the formed subchannel are determined by the type of transmission.

4. The method of claim 2, wherein the mapping of the modulated data symbols to the plurality of OFDM subcarriers in the subchannel is based on characteristics of the subframe.

5. The method of claim 2, wherein an inverse FFT is applied the OFDM subcarriers to generate a time-domain signal and the size of the inverse FFT is based on characteristics of the subframe.

6. The method of claim 2, wherein a cyclic prefix (CP) is added to each of the time-domain signals, wherein the length of the CP is based on characteristics of the subframe.

7. The method of claim 1, wherein pilot symbols are transmitted with the modulated data.

8. The method of claim 7, wherein phases and amplitudes of the pilot symbols are set based on the cell identity.

9. The method of claim 7, wherein the pilot symbols are mapped to OFDM subcarriers in the frequency channel based on the cell identity.

10. A base station in a cell of a multi-cell wireless system using a transmission frame structure, each frame comprising a plurality of subframes, each subframe comprising a plurality of time slots, each time slot comprising a plurality of orthogonal frequency division multiplexing (OFDM) symbols, the base station comprising a transmitter configured to:

broadcast a control signal containing a cell identity associated with the cell of the base station;

form a subchannel by selecting a plurality of OFDM subcarriers within a frequency channel in a time slot; and

transmit data over the subchannel to a mobile station in the cell, wherein;

the data are scrambled based on the cell identity;

the scrambled data are modulated to produce modulated data symbols; and

the modulated data symbols are mapped, based on the cell identity, to the plurality of OFDM subcarriers in the subchannel.

11. A method for a mobile station in a cell of a multi-cell wireless system using a transmission frame structure, each frame comprising a plurality of subframes, each subframe comprising a plurality of time slots, each time slot comprising a plurality of orthogonal frequency division multiplexing (OFDM) symbols, the method comprising:

transmitting a uplink signal to a serving base station in the cell, the uplink signal carrying control information, data packets, or both control information and data packets;

receiving, from the serving base station, a control signal containing a cell identity associated with the cell;

receiving, from the serving base station, data over a subchannel containing a plurality of orthogonal frequency division multiplexing (OFDM) subcarriers within a frequency channel in a time slot, wherein;

the received data were scrambled based on the cell identity;

the scrambled data were modulated to produce modulated data symbols; and

the modulated data symbols were mapped, based on the cell identity, to the plurality of OFDM subcarriers in the subchannel.

12. The method of claim 11, further comprising receiving pilot symbols with the received data.

13. The method of claim 12, wherein phases and amplitudes of the pilot symbols were determined based on the cell identity.

14. The method of claim 12, wherein the pilot symbols were mapped to OFDM subcarriers in the frequency channel based on the cell identity.

15. The method of claim 11, further comprising sending an acknowledgement (ACK) to the serving base station if the data was successfully received or a negative acknowledgement (NAK) to the serving base station if the data was unsuccessfully received.

16. A mobile station in a cell of a multi-cell wireless system using a transmission frame structure, each frame comprising a plurality of subframes, each subframe comprising a plurality of time slots, each time slot comprising a plurality of orthogonal frequency division multiplexing (OFDM) symbols, the mobile station comprising:

a transmitter configured to transmit an uplink signal to a serving base station in the cell, the uplink signal carrying control information, data packets, or both control information and data packets;

a receiver configured to receive, from the serving base station, a control signal containing a cell identity associated with the cell; and

a receiver configured to receive, from the serving base station, data over a subchannel containing a plurality of orthogonal frequency division multiplexing (OFDM) subcarriers within a frequency channel in a time slot, wherein;

the received data were scrambled based on the cell identity;

the scrambled data were modulated to produce modulated data symbols; and

the modulated data symbols were mapped, based on the cell identity, to the plurality of OFDM subcarriers in the subchannel.