US 12,449,714 B2 · Photonic analog-to-digital converter (pADC) with photonic phase correction

Abstract

A system and method for correcting environmental phase drift between signal and reference branches of a photonic analog-digital converter (pADC) with passive remote sampler (PRS) sends a continuous-wave (CW) laser from a base unit through the PRS in a reverse optical path to measure the phase drift. The CW optical signal is converted to an electrical signal from which a phase-error signal indicative of the phase drift is filtered out and sent to a phase shifter. The pADC sends an optical pulse through the PRS in a forward optical path; the signal pulse is phase-modulated according to a received radio frequency (RF) signal of interest. The phase-modulated optical pulses (e.g., signal and reference) are received at the base unit and the phase drift corrected out of the optical pulses via the phase shifter. The corrected optical pulses are demodulated to provide a digital counterpart to the RF signal of interest.

Claims15

Dependent claims

A photonic analog-digital converter (pADC), comprising:

a passive remote sampler (PRS) configured to:
receive at least one radio frequency (RF) signal of interest;
and
modulate at least one optical pulse according to the received RF signal of interest;
a base unit having a sending side and a receiving side, the sending side and the receiving side both optically coupled to the PRS,
the receiving side configured to:
measure a phase drift associated with the PRS by sending a continuous-wave (CW) optical signal through the PRS in a reverse optical path;
and
receive the at least one modulated optical pulse via the PRS;
the sending side comprising:
an optical pulse source configured to transmit the optical pulse through the PRS in a forward optical path;
and
at least one photodiode configured to convert the CW optical signal into an electrical signal indicative of the phase drift;
and
the receiving side configured to:
receive the electrical signal from the sending side;
and
correct the phase drift associated with the at least one modulated optical pulse based on the electrical signal.

15 more elements

A method for photonic phase correction in a photonic analog-digital converter (pADC), the method comprising:

receiving an RF signal of interest via a passive remote sampler (PRS) of the pADC;
sending a continuous-wave (CW) optical signal through the PRS in a reverse optical path;
converting the CW optical signal to an electrical signal at least partially indicative of an environmental phase drift associated with the PRS;
sending at least one optical pulse through the PRS in a forward optical path;
modulating, via a phase modulator of the PRS, the at least one optical pulse according to the received RF signal of interest;
and
correcting, via a receiving side of a base unit optically coupled to the PRS, the environmental phase drift from the at least one modulated optical pulse based on the converted electrical signal.

4 more elements

Dependencies are inferred from the claim text.

Photonic analog-to-digital converter (pADC) with photonic phase correction

Life of this patent

Photonic analog-to-digital converter (pADC) with photonic phase correction

Life of this patent

Abstract

Claims15