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Spectral-Efficiency Of Multi-Antenna Links In Ad-Hoc Networks With Limited Tx Csi, Siddhartan Govindasamy, Daniel Bliss, David Staelin
Spectral-Efficiency Of Multi-Antenna Links In Ad-Hoc Networks With Limited Tx Csi, Siddhartan Govindasamy, Daniel Bliss, David Staelin
Siddhartan Govindasamy
An asymptotic expression is derived for the mean spectral efficiency of multi-antenna links randomly distributed on a plane in a uniform manner where transmitters (Tx) have Channel-State-Information (CSI) of the channels between themselves and their target receivers while receivers (Rx) have CSI between themselves and all transmitters. The mean per-link spectral efficiency in the network is found to increase if nodes transmit using a subset of their strongest channel modes instead of the link-optimal strategy of water-filling on all channel modes (Farrokhi et al.). For reasonable parameters, this system which requires limited Tx CSI, has approximately double the mean spectral …
Spectral Efficiency In Single-Hop Ad-Hoc Wireless Networks With Interference Using Adaptive Antenna Arrays, Siddhartan Govindasamy, Daniel Bliss, David Staelin
Spectral Efficiency In Single-Hop Ad-Hoc Wireless Networks With Interference Using Adaptive Antenna Arrays, Siddhartan Govindasamy, Daniel Bliss, David Staelin
Siddhartan Govindasamy
Receivers with N antennas in single-hop, ad-hoc wireless networks with nodes randomly distributed on an infinite plane with uniform area density are studied. Transmitting nodes have single antennas and transmit simultaneously in the same frequency band with power P that decays with distance via the commonly-used inverse-polynomial model with path-loss-exponent (PLE) greater than 2. This model applies to shared spectrum systems where multiple links share the same frequency band. In the interference-limited regime, the average spectral efficiency of a representative link E[C] (b/s/Hz/link) is found to grow as log(N) and linearly with PLE, and its variance decays as 1/N. The …
The Performance Of Linear Multiple-Antenna Receivers With Interferes Distributed On A Plane, Siddhartan Govindasamy, Filip Antic, Daniel Bliss, David Staelin
The Performance Of Linear Multiple-Antenna Receivers With Interferes Distributed On A Plane, Siddhartan Govindasamy, Filip Antic, Daniel Bliss, David Staelin
Siddhartan Govindasamy
We find an asymptotic expression for the average signal to interference ratio (SIR) between a transmitter with a single isotropic antenna and a multi-antenna linear receiver in the presence of interferers with single isotropic transmit antennas distributed uniformly on an infinite plane. The channels are modeled as complex Gaussian random variables with average received power dependent on the distance separating nodes. We find that in large networks, the average SIR for a representative link depends primarily on the ratio of the number of receive antenna elements to the area density of interferers. Furthermore for our network model, the SIR grows …
Minimizing Hidden-Node Network Interference By Optimizing Siso And Mimo Spectral Efficiency, Daniel Bliss, Siddhartan Govindasamy
Minimizing Hidden-Node Network Interference By Optimizing Siso And Mimo Spectral Efficiency, Daniel Bliss, Siddhartan Govindasamy
Siddhartan Govindasamy
In this paper, the optimal spectral efficiency (data rate divided by the message bandwidth) that minimizes the probability of causing disruptive interference for ad hoc wireless networks or cognitive radios is investigated. Two basic problem constraints are considered: a given message size, or fixed data rate. Implicitly, the trade being optimized is between longer transmit duration and wider bandwidth versus higher transmit power. Both single-input single-output (SISO) and multiple-input multiple-output (MIMO) links are considered. Here, a link optimizes its spectral efficiency to be a “good neighbor.” The probability of interference is characterized by the probability that the signal power received …
Performance Of Multi-Antenna Mmse Receivers In Non-Homogeneous Poisson Networks, Junjie Zhu, Siddhartan Govindasamy
Performance Of Multi-Antenna Mmse Receivers In Non-Homogeneous Poisson Networks, Junjie Zhu, Siddhartan Govindasamy
Siddhartan Govindasamy
A technique to compute the Cumulative Distribution Function (CDF) of the Signal-to-Interference-plus-Noise-Ratio (SINR) for a wireless link with a multi-antenna, Linear, Minimum-Mean-Square-Error (MMSE) receiver in the presence of interferers distributed according to a non-homogenous Poisson point process on the plane, and independent Rayleigh fading between antennas is presented. This technique is used to compute the CDF of the SINR for several different models of intensity functions, in particular, power-law intensity functions, circular-symmetric Gaussian intensity functions and intensity functions described by a polynomial in a bounded domain. Additionally it is shown that if the number of receiver antennas is scaled linearly …