Wavelength selective switching for optical bandwidth management

40 Gb/s DBPSK and DQPSK formats for transparent 50 GHz DWDM transmission

“…The DQPSK format was generated using a commercial nested MZM that produced NRZ-DQPSK modulation using two parallel DBPSK modulators with a relative optical phase of p/2. In-phase (I) and quadrature (Q) signals were generated by multiplexing two copies (one copy shifted by 14 …”

“…This dense wavelength division multiplexed (DWDM) transport system at the higher channel rates allowed for the investigation and studies of several optical technologies and techniques for generating different modulation formats [12,16]. In addition to carrying higher data rates on a wavelength, today's networks are evolving from simple point-to-point and ring networks to highly interconnected mesh networks, where reconfigurable optical add/drop multiplexers (ROADMs) have become key enablers for transparent optical networking [2,6,14]. The ROADMs, built from optical elements such as wavelength selective switches (WSS), interleavers spaced system and an asymmetric bandwidth allocated 50 GHz spaced system [7].…”

Polarization-independent bidirectional 4×4 optical switch in free space

“…The major approaches include, the space-division optical switch [7][8][9], the wave-guide type optical switch [10][11][12], the silica-based switch [13][14][15], the thermo-optical switch [16][17][18], the acousto-optic routing switch [19][20][21], the optomechanical switch [22][23][24][25][26], the electro-optic switch [27,28], and the free space optical switch [29,30]. While they all offer the benefits associated with optical interconnection, they do exhibit drawbacks and limitations in practical applications.…”

Optical grooming switch with regenerative functionality for transparent interconnection of networks

“…Optical switching technologies, on the other hand, have the potential to overcome those issues. Compared to their electronic counterparts, optical switches are characterized by significantly lower power consumption and footprint, which leads to significant operational expenditures (OPEX) savings [6][7][8]. Furthermore, they can deal with significantly higher capacities (~1 Tbit/s) than normal IP routers [9,10].…”