An Optimum Hardware Detector for Constant Envelope Quadrature-Quadrature Phase Shift Keying (CEQ2OSK)

A hardware detector for constant envelope quadrature- quadrature phase-shift keying (CEQ2PSK) is proposed. It uses appropriate hard decisions; yet, it achieves optimum probability of bit error performance, unlike the suboptimum detector of Saha and Birdsall. This optimum performance is verified through Monte Carlo computer simulations. Additionally, a more correct expression is given for the probability of bit error performance for CEQ2PSK, which gives the gain over nonconstant Q2PSK as 1.44 dB, rather than the previously published value of 1.76 dB

A Novel Expanded 16-Dimensional Constant Envelope Q2PSK Constellation

We introduce a 16-dimensional constant-amplitude constellation that is generated by concatenating either four constant envelope quadrature-quadrature phase shift keying (CEQ2PSK) symbols from Saha and Birdsall or four CEQ2PSK symbols recently discovered by Cartwright and also introduced here. Our new constellation doubles the number of points available for data transmission without decreasing the distance between points or increasing energy, and may therefore be used in a trellis coded modulation (TCM) system without constellation expansion penalty. Because the new constellation has constant envelope, the modulation scheme becomes very attractive for nonlinear channels such as the magnetic recording channel or the satellite channel with traveling wave tube amplifiers

Blind Phase Recovery in Cross QAM Communication Systems with the Reduced Constellation Eigth-Order Estimator (RCEOE)

The eighth-order (EOE) phase estimator [4] is modified to work for an eight-symbol symmetrical constellation, so that the large signal-to-noise (SNR) performance is not limited by self-noise. By using only the eight highest energy points of cross- QAM constellations, a reduced constellation eighth-order estimator (RCEOE) is proposed. Computer simulations for 128-QAM show that this new method performs substantially better than the recently introduced APP phase estimator of Wang et al. [8]. However, simulations with 32-QAM show little performance advantage of the RCEOE over the APP estimator, for SNR values normally of interest, whereas for low SNR, the improvement is significant. Application to any constellation which can be reduced to an 8-symbol quadrant symmetrical sub-constellation is straightforward

Trellis Coded Modulation Schemes Using A New Expanded 16-Dimensional Constant Envelope Quadrature-Quadrature Phase Shift Keying Constellation

In this thesis, the author presents and analyzes two 4-dimensional Constant Envelope Quadrature-Quadrature Phase Shift Keying constellations. Optimal demodulators for the two constellations are presented, and one of them was designed and implemented by the author. In addition, a novel expanded 16-dimensional CEQ2PSK constellation that doubles the number of points without decreasing the distance between points or increasing the peak energy is generated by concatenating the aforementioned constellations with a particular method and restrictions. This original 16-dimensional set of symbols is set-partitioned and used in a multidimensional Trellis-Coded Modulation scheme along with a convolutional encoder of rate 2/3. Effective gain of 2.67 dB over uncoded CEQ2PSK constellation with low complexity is achieved theoretically. A coding gain of 2.4 dB with 8 dB SNR is obtained by using Monte Carlo simulations. The TCM systems and demodulators were tested under an Additive White Gaussian Noise channel by using Matlab\u27s Simulink block diagrams

Trellis Coded Modulation Schemes Using A New Expanded 16-Dimensional Constant Envelope Quadrature-Quadrature Phase Shift Keying Constellation

In this thesis, the author presents and analyzes two 4-dimensional Constant Envelope Quadrature-Quadrature Phase Shift Keying constellations. Optimal demodulators for the two constellations are presented, and one of them was designed and implemented by the author. In addition, a novel expanded 16-dimensional CEQ2PSK constellation that doubles the number of points without decreasing the distance between points or increasing the peak energy is generated by concatenating the aforementioned constellations with a particular method and restrictions. This original 16-dimensional set of symbols is set-partitioned and used in a multidimensional Trellis-Coded Modulation scheme along with a convolutional encoder of rate 2/3. Effective gain of 2.67 dB over uncoded CEQ2PSK constellation with low complexity is achieved theoretically. A coding gain of 2.4 dB with 8 dB SNR is obtained by using Monte Carlo simulations. The TCM systems and demodulators were tested under an Additive White Gaussian Noise channel by using Matlab\u27s Simulink block diagrams