Method and apparatus for preamble training in a multiple antenna communication system
AssigneeAgere Systems Inc.
InventorsSyed Aon Mujtaba, Xiaowen Wang
Life of this patent
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Abstract
Methods and apparatus are provided for communicating data in a multiple antenna communication system having N transmit antennas. According to one aspect of the invention, a header format includes a legacy preamble having at least one legacy long training field and an extended portion having at least N additional long training fields on each of the N transmit antennas. The N additional long training fields may be tone interleaved across the N transmit antennas and are used for MIMO channel estimation. The extended portion may include a short training field for power estimation. The short training field may be tone interleaved across the N transmit antennas and have an extended duration to support beam steering.
Claims24
A method for transmitting data in a multiple antenna communication system having N transmit antennas, said method comprising the steps of:
- obtaining a signal comprising a legacy preamble having at least one legacy long training field and at least one legacy short training field and an extended portion having in the range of one to N−1 additional long training fields on each of said N transmit antennas and at least one additional short training field, wherein each additional long training field contains one long OFDM symbol and N is greater than two, wherein said long OFDM symbol utilizes a frequency grid of M points and wherein a data OFDM symbol utilizes a frequency grid of M/2 points, and transmitting said signal.
A transmitter in a multiple antenna communication system, comprising:
- N transmit antennas configured to transmit a signal obtained by a transmitter circuit, the signal comprising a legacy preamble having at least one legacy long training field and at least one legacy short training field and an extended portion having in the range of one to N−1 additional long training fields on each of said N transmit antennas and at least one additional short training field, wherein each additional long training field contains one long OFDM symbol and N is greater than two, wherein said long OFDM symbol utilizes a frequency grid of M points and wherein a data OFDM symbol utilizes a frequency grid of M/2 points.
A method for receiving data on at least one receive antenna transmitted by a transmitter having N transmit antennas in a multiple antenna communication system, said method comprising the steps of:
- receiving a signal comprising a legacy preamble having at least one legacy long training field and at least one legacy short training field and an extended portion having in the range of one to N−1 additional long training fields on each of said N transmit antennas and at least one additional short training field, wherein each additional long training field contains one long OFDM symbol and N is greater than two, wherein said long OFDM symbol utilizes a frequency grid of M points and wherein a data OFDM symbol utilizes a frequency grid of M/2 points, and processing said signal.
A receiver in a multiple antenna communication system having at least one transmitter having N transmit antennas, comprising:
- at least one receive antenna configured to receive a signal comprising a legacy preamble having at least one legacy long training field and at least one legacy short training field and an extended portion having in the range of one to N−1 additional long training fields on each of said N transmit antennas and at least one additional short training field, wherein each additional long training field contains one long OFDM symbol and N is greater than two, wherein said long OFDM symbol utilizes a frequency grid of M points and wherein a data OFDM symbol utilizes a frequency grid of M/2 points, and a receiver circuit configured to process the received signal.
Dependencies are inferred from the claim text.