US 7,321,645 B2 | ||
Method and arrangement for detecting a random access channel preamble using multiple antenna reception in a communication system | ||
Jung Ah Lee, Pittstown, N.J. (US); and Anil M. Rao, Randolph, N.J. (US) | ||
Assigned to Lucent Technologies Inc., Murray Hill, N.J. (US) | ||
Filed on Aug. 29, 2003, as Appl. No. 10/651,200. | ||
Prior Publication US 2005/0047530 A1, Mar. 03, 2005 | ||
Int. Cl. H03D 1/00 (2006.01); H04L 27/06 (2006.01) |
U.S. Cl. 375—343 [375/134; 375/136; 375/137; 375/142; 375/145; 375/147; 375/150] | 20 Claims |
1. A method of detecting a random access channel preamble in a received uplink signal from a user, comprising:
spatially processing and temporally processing an uplink signal received at one or more receive antennas of a base station
receiver and containing data related to a random access channel preamble to detect the random access channel preamble, wherein
temporal processing includes:
temporally correlating the received uplink signal to output at least one subcorrelation output signal,
determining, for each subcorrelation output signal, a decision statistic as the magnitude squared of the subcorrelation output
signal, and
comparing a maximum of the determined decision statistics to a threshold value, the random access channel preamble of the
uplink signal having been detected if the maximum decision statistic meets or exceeds the threshold value, and
determining the threshold value so that as the number of antenna beams for a given angle of arrival of the received uplink
signal increase, the threshold value increases so as to maintain a probability of false alarm over all antenna beams to a
desired value, wherein the probability of false alarm is a probability that the uplink signal is falsely detected when no
random access channel preamble has been transmitted by the user.
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