kthRB [x.sub.k](m) [y.sub.k](m) [z.sub.k] = [h.sub.T] (m) 1 20 20 2 2 20 -20 2 3 -20 -20 2 4 -20 20 2 kthRB [f.sub.k] (kHz) Notes 1 2,399,800 Harmonic signal 2 2,399,850 Harmonic signal 3 2,399,900 Harmonic signal 4 2,400,100 DPSK
; RB + MR
The scheme does not need the pulse carver at DPSK
transmitter and can reduce deployment cost significantly.
Dynamic Pre-Shared Keys (DPSKs
) are a unique feature for organizations that aren't ready to wade into the deep end of Wi-Fi BYOD security with 802.1X.
The new design win is for 40 Gb/s long haul communications in dense wavelength division multiplexing (DWDM) systems that utilizes 40Gb/s DPSK
(differential phase-shift keying) modulation.
In 2009, GlobeNet upgraded a segment of its network with Xtera's NXT 20 Gbps Differential Phase Shift Key (DPSK
 Differential phase shift keying(DPSK
): A phase modulation scheme in which the phase of a signal is modulated by 180 degrees corresponding to the digital data of "0" or "1".
Assuming that similitude, the GMSK modulation can be demodulated as a two staggered quadrature modulated binary phase shift keying (PSK) signal, (7, 8, 9) or as a differential phase modulation (DPSK
), (8, 10) or as a frequency modulation.
The transmission breakthrough was made possible using the differential phase shift keying (DPSK
) method, a new coding scheme for high-capacity communications developed at Bell Labs.
Each transmitter consisted of an optical source with 9 dBm output power, the phase of the output radiation of which was modulated using a DPSK
modulator, which in its turn was driven by a flow of non-return-to-zero (NRZ) coded electrical pulses.
On the other hand, the performance of non-coherent technique, DPSK
and FSK, are almost equal to coherent PSK and coherent FSK .