SDPSK-Specific Demodulation Method for the Nanortu Field-Programmable Gate Array / SDPSK-Specifiska Demodulācijas Metode Nanortutm Programmētajām Loģiskajām Integrācijas Shēmām

The software-defined radio (SDR) solutions inpart flexibility to the satellite applications when the devices are physically inaccessible after the launch. The nanoRTU FPGA-based controller (AAC Microtec) may be programmed to serve as a software-defined differential phase shift keying (SDPSK) modem backend to be used in satellites for communication with the Earth. The modem consists of two units - a modulator and a demodulator. A fully functional symmetric SDPSK modulator for nanoRTU FPGA has already been implemented. The next step of the modem implementation is the development of demodulator. In order to implement such facilities, the existing demodulation techniques should be reviewed in order to propose the appropriate method in which the demodulator would be capable of demodulating a signal, and, at the same time, would be resource-efficient. The author describes a valid method of specific SDPSK signal demodulation for the nanoRTU FPGA.

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A geometric approach to higher-order differential phase shift keying

MILCOM 91 - Conference record ◽

10.1109/milcom.1991.258267 ◽

2002 ◽

Author(s):

D. van Alphen ◽

W.C. Lindsey

Keyword(s):

Phase Shift ◽

Geometric Approach ◽

Higher Order ◽

Phase Shift Keying ◽

Differential Phase Shift ◽

Differential Phase ◽

Differential Phase Shift Keying ◽

Shift Keying

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Design and Performance Analysis of 2D OCDMA System with Polarization States

Journal of Optical Communications ◽

10.1515/joc-2015-0094 ◽

2016 ◽

Vol 37 (4) ◽

Author(s):

Manisha Bharti ◽

Ajay K. Sharma ◽

Manoj Kumar

Keyword(s):

Phase Shift ◽

Polarization State ◽

Phase Shift Keying ◽

Modulation Formats ◽

Differential Phase Shift ◽

Differential Phase ◽

Differential Phase Shift Keying ◽

Shift Keying ◽

Polarization States ◽

Code Division Multiple

AbstractThis paper focuses on increasing the number of subscribers in optical code-division multiple access (OCDMA) system by using one of the features of light signal that it can be propagated in two polarization states. The performance of two-dimensional (2D) OCDMA system based on wavelength-time coding scheme by adding polarization state is investigated at varying data rates from 1 GHz to 6 GHz and for various modulation formats. It is reported that with increase in data rate of system, the performance of the system deteriorates due to polarization mode dispersion. Non-return to-zero (RZ), return to-zero (RZ), carrier suppressed return-to-zero (CSRZ) and differential phase shift keying (DPSK) modulation formats are simulated for a single user system with polarization. Investigations reveal that differential phase shift keying (DPSK) modulation format suits best to the proposed system and exhibit the potential to improve the flexibility of system for more number of users. The investigations are reported in terms of Q-factor, BER, received optical power (ROP) and eye diagrams.

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