26 research outputs found
Performance of DF Incremental Relaying with Energy Harvesting Relays in Underlay CRNs
In this paper, we analyze the throughput performance of incremental relaying
using energy harvesting (EH) decode-and-forward (DF) relays in underlay
cognitive radio networks (CRNs). The destination combines the direct and
relayed signals when the direct link is in outage. From the derived closed-form
expressions, we present an expression for the power-splitting parameter of the
EH relay that optimizes the throughput performance. We demonstrate that
relaying using EH DF relays results in better performance than direct
signalling without a relay only when the destination combines the direct signal
from the source with the relayed signal. Computer simulations demonstrate
accuracy of the derived expressions
Iterative receiver based on SAGE algorithm for crosstalk cancellation in upstream vectored VDSL
We propose the use of an iterative receiver based on the Space Alternating Generalized Expectation maximization (SAGE) algorithm for crosstalk cancellation in upstream vectored VDSL. In the absence of alien crosstalk, we show that when initialized with the frequency-domain equalizer (FEQ) output, the far-end crosstalk (FEXT) can be cancelled with no more real-time complexity than the existing linear receivers. In addition, the suggested approach does not require offline computation of the channel inverse and thus reduces the receiver complexity. In the presence of alien crosstalk, there is a significant gap between the rate performance of the linear receivers as compared with the single-user bound (SUB). The proposed receiver is shown to successfully bridge this gap while requiring only a little extracomplexity. Computer simulations are presented to validate the analysis and confirm the performance of the proposed receiver
Blind subspace DOA estimation in multipath DS/CDMA channels
In this paper, we consider the problem of blind estimation of the directions of arrival (DOA's) of users' paths in a multipath DS/CDMA channel. Making use of the signal that is sampled at multiple antenna elements and using a subspace based MUSIC-like technique, we show the possibility of DOA estimation using two search methods. The first provides path delays and DOAs simultaneously, and the second provides only DOAs. Knowledge of the chip waveform is used in the first method. It is seen that the two methods exhibit good estimation accuracy, besides being extremely near-far resistant