Method and apparatus to detect random access channel preamble
AssigneeNokia Siemens Networks Oy
InventorJukka Tormalehto
Life of this patent
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Abstract
A method (and operation of a computer program) includes receiving a signal over a wireless channel; correlating the received signal with a reference sequence and providing a correlation output; processing the correlation output to detect a presence of a first predetermined preamble sequence using a main correlation peak and two first order frequency shift peaks and nulling second and higher order frequency shift peaks from the correlation output prior to further processing the correlation output to detect a presence of a second predetermined preamble sequence. Apparatus that embody the method are also disclosed.
Claims25
A method, comprising:
- receiving a signal over a wireless channel;
- correlating the received signal with a reference sequence and providing a correlation output;
- processing the correlation output to detect a presence of a first predetermined preamble sequence using a main correlation peak and two first order frequency shift peaks;
- and
- nulling second and higher order frequency shift peaks from the correlation output prior to further processing the correlation output to detect a presence of a second predetermined preamble sequence.
A computer-readable memory medium that stores program instructions the execution of which results in operations that comprise:
- correlating a received signal with a reference sequence and providing a correlation output;
- processing the correlation output to detect a presence of a first predetermined preamble sequence using a main correlation peak and two first order frequency shift peaks;
- and
- nulling second and higher order frequency shift peaks from the correlation output prior to further processing the correlation output to detect a presence of a second predetermined preamble sequence.
An apparatus, comprising
- a wireless receiver;
- a correlator configurable to correlate a received signal with a reference sequence to provide a correlation output;
- and
- a processor configurable to process the correlation output in the time domain to detect a presence of a first predetermined preamble sequence using a main correlation peak and two first order frequency shift peaks, said processor further configurable to null higher order frequency shift peaks from the correlation output prior to further processing the correlation output to detect a presence of a second predetermined preamble sequence.
Dependencies are inferred from the claim text.