Recently, the authors of [1] have presented the Stokes-vector direct detection transceiver as a promising candidate for noncoherent short-haul fiber-optic communication. Their method was improved by MorsyOsman, et al. in [2] to exploit all four transmitted signal-space dimensions, but their proposed methods for detecting the fourth dimension all suffer various practical drawbacks. In this paper...

A loss of subchannel orthogonality due to timevariant multipath channels in orthogonal frequency-division multiplexing (OFDM) systems leads to interchannel interference (ICI) which increases the error floor in proportion to the Doppler frequency. In this paper, a simple frequency-domain equalization technique which can compensate for the effect of ICI in a multipath fading channel is proposed. ...

This report describes the analysis of the link adaptation strategy for non-binary LDPC codes in a multicarrier system over a time-variant frequency-selective channel. The transmitted power is equally distributed over a subset of subchannels that are identified through the waterfilling technique. Then the modulation order is adapted to each subchannel in order to increase the throughput of the s...

An optimal subcarrier allocation algorithm is proposed for orthogonal frequency division multiple access systems over Rayleigh fading channels with channel state information feedback. The transmitted orthogonal frequency division multiple access frame is divided into groups called subchannels according to the detected number of users at the base station. The pilots are reduced for the stable su...

We begin with a detailed description of a low dimensional quantum channel (dA = 4, dE = 3) demonstrating the symmetric form of superactivation of one-shot zero-error quantum capacity. This means appearance of a noiseless (perfectly reversible) subchannel in the tensor square of a channel having no noiseless subchannels. Then we describe a quantum channel Φ such that Q̄0(Φ) = 0 and Q̄0(Φ⊗ Φ) ≥ log...

Per tone equalization was recently proposed as an alternative equalization structure for multicarrier systems. In this paper we propose two NLMS based variable length per tone equalization algorithms. In the first algorithm, the number of equalizer taps used in every subchannel is determined according to channel conditions which results in a reduction in equalization complexity. While the secon...

We present an algorithm for design of a joint source-channel coder using a channel-optimized quantizer and multicarrier modulation. By changing the power of each subchannel in the multicarrier modulation system, different degrees of error protection can be provided for different bits according to their importance. The algorithm converges to a locally optimum system design. Compared to a Lloyd–M...