Detecting the number of transmit antennas in a base station

• US 8,494,090 B2
• Filed: 09/10/2012
• Issued: 07/23/2013
• Est. Priority Date: 08/07/2007
• Status: Active Grant

• Current Assignee: Blackberry Limited
• Original Assignee: Blackberry Limited
• Inventors: Callard, Aaron, Ma, Jianglei
• Primary Examiner(s): Fotakis, Aristocratis
• Application Number:
  US13/608,184
• Publication Number:
  US 20130003893A1
• Time in Patent Office: 316 Days
• Field of Search: 375/150, 375/299, 375/365, 375/340, 370/203, 370/208, 370/350, 455/500, 714/758, 714/759, 714/760, 714/807
• US Class Current: 375/299
• CPC Class Codes: H04B 7/0678 using different spreading codes between antennas code allocation H04J13/16
• CPC Class Codes: H04B 7/0689 using different transmission schemes, at least one of them being a diversity transmission scheme
• CPC Class Codes: H04L 5/0092 Indication of how the channel is divided
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/30 Resource management for broadcast services

Abstract

Data is scrambled at a transmitter according to one of a number of predetermined scrambling sequences which are associated with a particular one of a number of predetermined transmit antenna diversity schemes (i.e., a specific number of transmit antenna ports). Received data is decoded using one or more of the known transmit antenna diversity schemes and the scrambled data is descrambled according to a corresponding descrambling sequence (related to the scrambling sequence). Based on the descrambled data, the receiver determines which transmit antenna diversity scheme (i.e., the number of antenna ports) is used by the transmitter. In one specific embodiment, CRC parity data is scrambled in the transmitter and the receiver descrambles the recovered CRC parity data according to a descrambling sequence, computes CRC parity data from the received data, and compares the descrambled CRC parity data to the newly computed CRC parity data.

Claims

1. A method comprising:

scrambling a plurality of bits of broadcast channel data using a first scrambling sequence when a transmitter operates with only one transmit antenna and using a second scrambling sequence when the transmitter operates with only two transmit antennas, wherein the first scrambling sequence indicates one transmit antenna operation and the second scrambling sequence indicates two transmit antenna operation; and

transmitting the plurality of scrambled bits within a data frame to a remote communication device,

wherein transmitting the plurality of scrambled bits further comprises transmitting the plurality of scrambled bits within a primary broadcast channel in accordance with a Long Term Evolution (LTE) standard.

2. The method of claim 1, wherein the broadcast channel data comprises transport data and cyclic redundancy check (CRC) data, wherein the CRC data is computed based on the transport data.

3. The method of claim 1, further comprising generating the broadcast channel data.

4. The method of claim 1, wherein the plurality of scrambled bits are transmitted using a plurality of resource elements.

5. The method of claim 1, wherein the primary broadcast channel uses seventy-two subcarriers.

6. A communications device for communicating with a remote communication device in a wireless network, the communications device configured to:

scramble a plurality of bits of the broadcast channel data using a first scrambling sequence when the communications device operates with only one transmit antenna and using a second scrambling sequence when the communications device operates with only two transmit antennas, wherein the first scrambling sequence indicates one transmit antenna operation and the second scrambling sequence indicates two transmit antenna operation; and

transmit the plurality of scrambled bits within a data frame to the remote communication,

wherein the communications device transmits the plurality of scrambled bits within a primary broadcast channel in accordance with a Long Term Evolution (LTE) standard.

7. The communications device of claim 6, wherein the broadcast channel data comprises transport data and cyclic redundancy check (CRC) data, wherein the CRC data is computed based on the transport data.

8. The communications device of claim 6, further configured to generate the broadcast channel data.

9. The communications device of claim 6, wherein the plurality of scrambled bits are transmitted using a plurality of resource elements.

10. The communications device of claim 6, wherein the primary broadcast channel uses seventy-two subcarriers.

11. A method for use with long term evolution (LTE) broadcast channel data, the method comprising:

scrambling at least a portion of the LTE broadcast channel data; and

transmitting at least the scrambled LTE broadcast channel data using at least one antenna, wherein the scrambling sequence used for scrambling is dependent upon the number of antenna used for said transmitting, the scrambling sequence associated with a particular number of antennas is unique, and the scrambled LTE broadcast channel data is transmitted within a data frame,

wherein transmitting at least the scrambled LTE broadcast channel data further comprises transmitting at least the scrambled LTE broadcast channel data within a primary broadcast channel in accordance with a Long Term Evolution (LTE) standard.

12. The method of claim 11, wherein scrambling at least a portion of LTE broadcast channel data comprises scrambling the portion of LTE broadcast channel data using a first scrambling sequence when said transmitting uses only one antenna and using a second scrambling sequence when said transmitting uses only two antennas.

13. The method of claim 11, wherein the LTE broadcast channel data comprises transport data and cyclic redundancy check (CRC) data, wherein the CRC data is computed based on the transport data.

14. The method of claim 11, further comprising generating the LTE broadcast channel data.

15. The method of claim 11, wherein the primary broadcast channel uses seventy-two subcarriers.

16. A communications device for transmitting Long Term Evolution (LTE) broadcast channel data to a remote communication device in a wireless network, the communications device configured to:

scramble at least a portion of the LTE broadcast channel data; and

transmit at least the scrambled LTE broadcast channel data using at least one antenna, wherein the communications device scrambles the at least a portion of LTE broadcast channel data using a scrambling sequence based on the number of antenna used for transmitting, the scrambling sequence associated with a particular number of antennas is unique, and the scrambled LTE broadcast channel data is transmitted within a data frame,

wherein the communications device is configured to transmit at least the scrambled LTE broadcast channel data within a primary broadcast channel in accordance with a long term evolution (LTE) standard.

17. The communications device of claim 16, wherein the communications device is configured to scramble the at least a portion of LTE broadcast channel data using a first scrambling sequence when the communications device transmits using only one antenna and using a second scrambling sequence when the communications device transmits using only two antennas.

18. The communications device of claim 16, wherein the LTE broadcast channel data comprises transport data and cyclic redundancy check (CRC) data, wherein the CRC data is computed based on the transport data.

19. The communications device of claim 16, wherein the communications device is further configured to generate the LTE broadcast channel data.

20. The communications device of claim 16, wherein the primary broadcast channel uses seventy-two subcarriers.