In this paper, we present a review on silicon-based nonlinear devices for all optical nonlinear processing of complex telecommunication signals. We discuss some recent developments achieved by our research group, through extensive collaborations with academic partners across Europe, on optical signal processing using silicon-germanium and amorphous silicon based waveguides as well as novel mate...

Broadband application of wireless communication calls for good signal to noise ratio (SNR) and variable high data rates. In the midst of a spate of available techniques, Orthogonal Frequency Division Multiplexing (OFDM) has proven to be effective. OFDM systems have high tolerance towards multipath effects in fading channels. Wireless communication will become tortuous in the presence of Inter S...

The High Rate Baseband Multi-Modulator (HRBM) ASIC is being developed to provide High-Speed Bandwidth Efficient Modulations to NASA missions. Bandwidth efficiencies from 2.0 bits/symbol/Hz to 2.75 bits/symbol/Hz are selectable from three CCSDS modulations: Gaussian Minimum Shift Keying (GMSK), Filter Offset Quadrature Phase Shift Keying (Filtered-OQSK) and 8-Phase Shift Keying Trellis Coded Mod...

Fifth generation (5G) wireless networks must meet the needs of emerging technologies like Internet Things (IoT), Vehicle-to-everything (V2X), Video on Demand (VoD) services, Device to communication (D2D) and many other bandwidth-hungry multimedia applications that connect a huge number devices. 5G demand better bandwidth efficiency, high data rates, low latency, reduced spectral leakage. To the...

We report on all-optical wavelength conversion of a 56 Gb/s differential quadrature phase shift keying signal and a 42.7 Gb/s on-off keying signal. Wavelength conversion is based on four-wave mixing effect in a 1 m long highly nonlinear GeAsSe chalcogenide fiber. The high nonlinearity of the fiber allows low-power penalty operation with a total average power of less than 60 mW.

Polarization-insensitive (PI) phase-transmultiplexing (PTM) of a 10-Gb/s return-to-zero ON-OFF keying (RZ-OOK) pump and a 10-Gb/s RZbinary phase-shift keying (RZ-BPSK) probe to 20-Gb/s RZ-quadrature-PSK (RZ-QPSK) has been successfully demonstrated for the first time in a passive, birefringent AlGaAs waveguide, utilizing PI cross-phase modulation (PI-XPM). For differential QPSK (DQPSK)-detection...

We show that, similar to the trellis-coded modulation representation of MIL-STD shaped offset quadrature phase-shift keying (SOQPSK), offset quadrature phaseshift keying (OQPSK) can be decomposed into a “degraded” trellis encoder and a memoryless mapper. Based on the representations of OQPSK and MIL-STD SOQPSK as trellis-coded modulations, we investigate the potential coding gains achievable fr...

In this paper, the performance of orthogonal frequency division multiple access (OFDMA) uplink systems over time-varying frequency-selective Rayleigh fading channels is investigated. Expressions of the bit error rate (BER) performance for quadrature phase shift keying (QPSK) and quadrature amplitude modulation (QAM) signals under channel estimation errors are derived. Based on BER performance, ...

In this paper, introduced below are the concepts of digital modulation used in many communication systems today. Techniques described include quadrature phase shift keying (QPSK) and quadrature amplitude modulation (QAM) and how these techniques can be used to increase the capacity and speed of a wireless network. These modulation techniques are the basis of communications for systems like cabl...

This paper presents new visualization techniques for 4D Quadrature-Quadrature Phase Shift Keying (QPSK), Saha’s Constant Envelope (CE) QPSK, and Cartwright’s CEQPSK in ideal bandlimited channels. The signal diagrams analyzed are: time-signal eye patterns for 4D passband signals, 2D complex trajectory diagrams of baseband signals, and time-signal eye patterns for the 1D outputs of the baseband m...