Acquisition of a gated pilot signal with coherent and noncoherent integration

A correlator, comprising:

• a buffer configured to receive first and second signals separated in time;
• a multiplier configured with the buffer to produce a plurality of product values from each of the first and second signals and a generated signal;
• a first adder configured with the multiplier to coherently combine portions of the product values produced from the first signal and coherently combine portions of the product values produced from the second signal;
• a second adder configured to noncoherently combine the coherently combined portions of the product values produced from the first signal to produce a first value and to noncoherently combine the coherently combined portions of the product values produced from the second signal to produce a second value;
• and
• a third adder configured to noncoherently combine the first and second values.

A correlator, comprising:

• means for receiving first and second signals separated in time;
• means for producing a plurality of product values from each of the first and second signals and a generated signal;
• means for coherently combining portions of the product values produced from the first signal and coherently combining portions of the product values produced from the second signal;
• means for noncoherently combining the coherently combined portions of the product values from the first signal to produce a first value and noncoherently combining the coherently combined portions of the product values from the second signal to produce a second value;
• and
• means for noncoherently combining the first and second values.

Computer-readable media embodying a program of instructions executable by a computer program to perform a method of correlation, the method comprising:

• receiving first and second signals separated in time;
• producing a plurality of product values from each of the first and second signals and a generated signal;
• coherently combining portions of the product values produced from the first signal and noncoherently combining those coherently combined portions to produce a first value;
• coherently combining portions of the product values produced from the second signal and noncoherently combining those coherently combined portions to produce a second value;
• and
• noncoherently combining the first and second values.

A method of acquiring a pilot signal, comprising:

• transmitting first and second pilot signals separated in time from a remote source;
• receiving the first and second signals;
• producing a plurality of product values from each of the pilot signals and a generated signal;
• coherently combining portions of the product values produced from the first pilot signal and noncoherently combining those coherently combined portions to produce a first value;
• coherently combining portions of the product values produced from the second pilot signal and noncoherently combining those coherently combined portions to produce a second value;
• and
• noncoherently combining the first and second values.

A communications system, comprising:

• a transmitter configured to transmit first and second pilot signals separated in time;
• and
• a receiver configured to receive the pilot signals, the receiver comprising,
• a multiplier configured to produce a plurality of product values from each of the first and second pilot signals and a generated signal;
• a first adder configured with the multiplier to coherently combine portions of the product values produced from the first signal and coherently combine portions of the product values produced from the second signal;
• a second adder configured to noncoherently combine the coherently combined portions of the product values produced from the first signal to produce a first value and to noncoherently combine the coherently combined portions of the product values produced from the second signal to produce a second value;
• and
• a third adder configured to noncoherently combine the first and second values.