APPARATUS AND METHOD FOR DETERMINING SIGNAL CORRELATION
An apparatus and a method for determining signal correlation, the method including: inputting a first signal to a first electro-optical conversion unit, to enable the first electro-optical conversion unit to modulate to-be-modulated light according to the input first signal and to obtain a to-be-measured signal; inputting a second signal to a second electro-optical conversion unit, to enable the second electro-optical conversion unit to modulate to-be-modulated light according to the input second signal and to obtain a correlation signal; determining a product signal of the to-be-measured signal and the correlation signal via a photoelectric method or an optical method; and determining correlation of the to-be-measured signal and the correlation signal by performing an electrical average operation on the product signal. Therefore, correlation of two high-speed signals is obtained by only using a low-bandwidth electrical device without requiring use of a large-bandwidth multiplier.
1 . An apparatus for determining signal correlation, comprising:
a memory; and
a processor coupled to the memory to:
input a first signal to a first electro-optical conversion unit, to enable the first electro-optical conversion unit to modulate to-be-modulated light according to the first signal and to obtain a to-be-measured signal;
input a second signal to a second electro-optical conversion unit, to enable the second electro-optical conversion unit to modulate to-be-modulated light according to the second signal and to obtain a correlation signal;
determine a product signal of the to-be-measured signal and the correlation signal via a photoelectric method or an optical method; and
determine correlation of the to-be-measured signal and the correlation signal by performing an electrical average operation on the product signal.
2 . The apparatus according to claim 1 , wherein the first electro-optical conversion unit is a transmitter, or a partial modulation unit of a transmitter.
3 . The apparatus according to claim 1 , wherein the second electro-optical conversion unit outputs a finite number of states.
4 . The apparatus according to claim 1 , wherein the first electro-optical conversion unit and the second electro-optical conversion unit are connected in parallel;
the first electro-optical conversion unit outputs an optical signal of the to-be-measured signal, and the second electro-optical conversion unit outputs an optical signal of the correlation signal; and
the processor comprises a photoelectric multiplier, the photoelectric multiplier being used to:
perform photoelectric conversion and a multiplication operation on a sum of the optical signal of the to-be-measured signal and the optical signal of the correlation signal, to obtain the product signal.
5 . The apparatus according to claim 4 , wherein the first electro-optical conversion unit and the second electro-optical conversion unit are modulation units of different modulators; or
the first electro-optical conversion unit and the second electro-optical conversion unit are different modulation units of a same modulator.
6 . The apparatus according to claim 1 , wherein the first electro-optical conversion unit and the second electro-optical conversion unit are connected in series;
a product of an optical signal of the to-be-measured signal and an optical signal of the correlation signal is output after the first electro-optical conversion unit and the second electro-optical conversion unit are connected in series; and
the processor comprises a photoelectric conversion unit, the photoelectric conversion unit being used to:
perform photoelectric conversion on the product of the optical signal of the to-be-measured signal and the optical signal of the correlation signal, to obtain the product signal.
7 . The apparatus according to claim 6 , wherein the first electro-optical conversion unit and the second electro-optical conversion unit are modulation units of different modulators.
8 . The apparatus according to claim 1 , wherein the product signal is a first product signal the apparatus further comprises:
a multiplication unit, configured to multiply the second signal with a low-frequency square wave before the second signal is input to the second electro-optical conversion unit, to obtain a second product signal; and
the processor is further used to:
input the second product signal to the second electro-optical conversion unit, to enable the second electro-optical conversion unit to modulate to-be-modulated light according to the second product signal and to obtain the correlation signal.
9 . The apparatus according to claim 8 , wherein the multiplication unit is a first multiplication unit and the apparatus further comprises:
a second multiplication unit, configured to multiply the first product signal with the low-frequency square wave before an electrical average operation is performed on the first product signal, to obtain a third product signal; and
the processor is further used to:
determine correlation of the to-be-measured signal and the correlation signal by performing the electrical average operation on the third product signal obtained by multiplying the first product signal with the low-frequency square wave.
10 . A method for determining signal correlation, comprising:
inputting a first signal to a first electro-optical conversion unit, to enable the first electro-optical conversion unit to modulate to-be-modulated light according to the first signal and to obtain a to-be-measured signal;
inputting a second signal to a second electro-optical conversion unit, to enable the second electro-optical conversion unit to modulate to-be-modulated light according to the input second signal and to obtain a correlation signal;
determining a product signal of the to-be-measured signal and the correlation signal via a photoelectric method or an optical method; and
determining correlation of the to-be-measured signal and the correlation signal by performing an electrical average operation on the product signal.