orthogonal frequency division multiplexing (ofdm) has become a promising method for many wireless communication applications. however, one main drawback of ofdm systems is the high peak-to-average power ratio (papr). selected mapping (slm) is a well-known technique to decrease the problem of high papr in ofdm systems. in this method, transmitter is obliged to send some bits named side informati...

Convolutional code is relatively popular technique in decreasing the bit error rate (BER). The transmitted data under Additive white Gaussian noise (AWGN) channel can be successfully recovered at the receiver side by using Viterbi algorithm based on hidden Markov model (HMM) to decode and correct the data. Viterbi algorithm work by calculating the hamming distance, comparing the path metric, an...

We designed, built, and demonstrated a novel OCDMA multi code transmitter and receiver capable of a Gigabit operation, runs error free with a capability of a bit-to-bit code swapping using fast wavelength-hopping time-spreading OCDMA codes. BER less than 10 was measured and no error floor was observed. By implementing optical layer XOR, our novel transmitter/receiver pair enables One-time Pad d...

A orthogonal decomposition of a general wideband space-time multipath channel is derived assuming antenna arrays at both the transmitter and receiver. Knowledge of channel state information at the transmitter is used to decompose the channel. This decomposition serves as a framework for eeciently managing the degrees of freedom in the space-time channel to trade-oo diversity and throughput. Sig...

The use of a blind scheme for suppressing interference in direct-sequence code-division multiple-access (DS /CDMA) communication systems is investigated. In particular, we use a blind version of the partial-bit DS/CDMA receiver to successfully suppress narrow-band and nearfar multiple-access interference without requiring knowledge of other users’ spreading codes, timing or phase information. P...

In this paper, we address iterative receiver processing for OFDM code division multiplexing (OFDM-CDM). The receiver algorithm we focus on is soft parallel interference cancellation in combination with a-priori demodulation. We investigate the convergence behavior of OFDM-CDM as a serial code concatenation, consisting of CDM as inner code and rate-1/2 convolutional codes as outer codes, by mean...

Multiple-Input Multiple-Output (MIMO) systems have been emerged as a technical breakthrough for high-data-rate wireless transmission. The performance of MIMO system can be improved by using different antenna selection so as to provide spatial diversity. In this paper, the performance of MIMO system over AWGN (Additive White Gaussian Noise) and Rician fading channels with ZF receiver is analyzed...

We propose a one-round 1-out-of-n computationally-private information retrieval protocol for `-bit strings with low-degree polylogarithmic receivercomputation, linear sender-computation and communication Θ(k · log n + ` · log n), where k is a possibly non-constant security parameter. The new protocol is receiver-private if the underlying length-flexible additively homomorphic public-key cryptos...

In this paper, a four channel Coarse Wavelength Division Multiplexing (CWDM) network is designed by incorporating the proposed and designed Two Dimensional (2D) Photonic Crystal Ring Resonator (PCRR) based Add Drop Filter (ADF). The performance parameters of the network such as the received output power, Bit Error Rate (BER) and Q factor are examined for the bit rate of 10 Gbps over the fiber l...

In a chaos-shift-keying (CSK) digital communication system, correlators followed by a comparator are typically used for coherent detection of the signal. Such a detection method, however, does not take the temporal variation of the bit energy into consideration. In this paper, an optimum detection for a binary CSK system is derived, taking into account the temporal variation of the bit energy f...