FSK With Limiter-Discriminator Detector in Nakagami Fading Channels With and Without Selection Combining

In this paper, an equation for the error probability of M-ary frequency shift keying with limiter-discriminator detection in Nakagami fading channels for arbitrary m is derived. The authors do the same for selection combining with L diversity channels for integer m and for switch and stay combining with two diversity channels for m=1 (Rayleigh fading). The error probability for various values of m, L, frequency deviation, and filter bandwidth is computed     

Capacity of correlated nakagami-m fading channels with diversity combining techniques

We derive closed-form expressions for the capacity of dual-branch maximal ratio combining, equal gain combining, selection combining, and switch and stay combining (SSC) diversity systems over correlated Nakagami-m fading channels. Because the final capacity expressions contain infinite series, we truncate the series and present upper bounds on the truncation errors. We also derive an expression that can be used to numerically determine the optimum adaptive switching threshold for the capacity of a dual-branch SSC system over correlated Nakagami-m fading channels. However, a closed-form expression for the optimum adaptive switching threshold is derived for the case of independent branches. The corresponding expressions for Rayleigh fading are obtained as a special case of Nakagami-m fading. Finally, numerical examples are presented for illustration.     

Application of turbo codes in satellite mobile systems

Turbo codes are considered in a mobile channel with FSK modulation and LDI detection. Numerical results are presented for narrowband Gaussian, land mobile and satellite mobile channels separately. Numerical results show that turbo codes can significantly improve the performance over uncoded signalling     

Baseband pulse shaping in CPFSK modulation

The performance of M-ary pulse shaped signals is compared with that of CPFSK signals in a narrowband channel at modulation index 1/M. Three symbol by symbol detection techniques are considered for signal detection. It is shown that M-ary pulse shaped signals perform significantly better than M-ary CPFSK signals, and are significantly less sensitive to symbol timing errors.<>     

Nonlinear continuous phase modulation

A class of nonlinear CPM signals is introduced by extending nonlinear CPFSK signals to other forms of frequency pulses. The distance results and spectral properties of nonlinear CPM signals are reported. Bit error probabilities of nonlinear CPM signals are simulated in presence of adjacent channel interference     

Economic Transmission Planning Model Suitable for a Regulated Network Service Provider

Conventional transmission planning models are subject to constant debate in the context of competitive markets, due to the functional unbundling of transmission sector from generation and distribution sectors and due to the new environment regulations. A value-based transmission planning model is proposed, suitable for an unbundled transmission network service provider having no assets in the generation sector. The model minimizes the long-term transmission investment costs and the expected social costs incurred to its clients, energy producers, and consumers, in the power auctions due to transmission bottlenecks. The uncertainties involved when incorporating short-term market models into long-term planning models are modeled with probabilistic representations for the bid prices, the component availabilities, and the hourly load variations. These features make this model suitable in the new environment paradigm. Generalized Benders decomposition technique with nonsequential Monte Carlo technique is employed to solve the final stochastic mixed-integer optimization model. Case studies are given to illustrate the performance of this model by implementing it in the modified Garver’s six-bus test system and the IEEE 24-bus reliability test system for a single planning year.     

GMSK with limiter-discriminator detector in Nakagami fading channel with and without selection combining

We derive an equation for the bit-error probability (BEP) of Gaussian minimum-shift keying with limiter discriminator detection in Nakagami-m fading channels including selection and switch-and-stay combining. We compute the BEP for various selections of system parameters.     

Non-coherent detectors for quadrature-multiplexed continuous phase modulation signals

Here, non-coherent detectors for quadrature-multiplexed continuous phase modulation (QM-CPM) signals are developed (Fonseka et al., 2008). QM-CPM signals are more spectrally efficient than CPM signals, and multiamplitude QM-CPM signals can be constructed that outperform QAM. The non-coherent detectors view a QM-CPM signal as having composite states that represent the information modulated both onto the in-phase and quadrature-phase carriers. Viterbi decoding is used to jointly detect the quadrature-multiplexed signal components. Optimal sequence-based quadrature-matched filter (QMF) detectors are presented for use with QM-CPM detection and a QM-MSK detector is developed in detail. Differential phase and envelope (DPE) detectors are also presented which require less computation and are able to outperform the QMF-type detectors when the unknown carrier phase varies (phase jitter, phase hits etc.) within the sequence length used in the sequence-based QMF detectors. In the absence of these phase fluctuation effects, as the sequence length used in the QMF detectors increases, the performance of the QMF detectors approaches the performance of optimal non-coherent detection. The DPE-type detectors perform within about 2.5 dB of optimal coherent detection.     

Improved mapping policy for reducing error coefficient in CPFSK signals

An improved mapping policy is introduced that alternates between standard and inverted bit mapping functions at selected phase states to reduce the error coefficient of continuous phase frequency shift keying (CPFSK) signals. The proposed policy can be applied to many different forms of CPFSK signals. It is demonstrated that the mapping policy can significantly improve performance, particularly at lower to moderate SNR values.     

Multi-h phase codes for continuous phase modulation

The best multi-h phase codes which produce the highest minimum Euclidean distance are reported at preselected numbers of states. 2-h, 3-h and 4-h signals are considered in the code search. Numerical results are presented separately for binary full-response and partial-response signals, with a rectangular and a raised cosine baseband pulse.<>