An Optical-Electrical Sub-Sampling Receiver Employing Continuous-Time ΔΣ Modulation

Abstract

Abstract-An optical-electrical sub-sampling down-conversion receiver architecture leveraging low-jitter optical sampling is described.A simple interface between the optical and electrical domains is accomplished by combining a photodiode with a second-order continuous-time ∆Σ modulator. A prototype system implemented in 0.18 µm CMOS achieving 36.4 dB SNR in a 2 MHz BW with an OSR of 250 is demonstrated.

Digital coherent receiver employing photonic downconversion for phase modulated radio-over-fibre links

“…One of the challenges associated with the digital demodulation techniques are the high sampling rates and bandwidth limitations of Analog-to-Digital (A/D) converters. Bandwidth and dynamic range limitations of A/D converters limit the operating range of coherent receivers using digital demodulation techniques up to few GHz [9,10]. One way to extend the frequency range of digital coherent receivers beyond few GHz is to use photonic downconversion as reported in [9][10][11] and references therein.…”

“…Bandwidth and dynamic range limitations of A/D converters limit the operating range of coherent receivers using digital demodulation techniques up to few GHz [9,10]. One way to extend the frequency range of digital coherent receivers beyond few GHz is to use photonic downconversion as reported in [9][10][11] and references therein. with digital coherent demodulation for phase modulated radioover-fibre links has been reported in [10].…”