3,338 research outputs found
Deep Q-Learning for Self-Organizing Networks Fault Management and Radio Performance Improvement
We propose an algorithm to automate fault management in an outdoor cellular
network using deep reinforcement learning (RL) against wireless impairments.
This algorithm enables the cellular network cluster to self-heal by allowing RL
to learn how to improve the downlink signal to interference plus noise ratio
through exploration and exploitation of various alarm corrective actions. The
main contributions of this paper are to 1) introduce a deep RL-based fault
handling algorithm which self-organizing networks can implement in a polynomial
runtime and 2) show that this fault management method can improve the radio
link performance in a realistic network setup. Simulation results show that our
proposed algorithm learns an action sequence to clear alarms and improve the
performance in the cellular cluster better than existing algorithms, even
against the randomness of the network fault occurrences and user movements.Comment: (c) 2018 IEEE. Personal use of this material is permitted. Permission
from IEEE must be obtained for all other uses, in any current or future
media, including reprinting/republishing this material for advertising or
promotional purposes, creating new collective works, for resale or
redistribution to servers or lists, or reuse of any copyrighted component of
this work in other work
Partially Blind Handovers for mmWave New Radio Aided by Sub-6 GHz LTE Signaling
For a base station that supports cellular communications in sub-6 GHz LTE and
millimeter (mmWave) bands, we propose a supervised machine learning algorithm
to improve the success rate in the handover between the two radio frequencies
using sub-6 GHz and mmWave prior channel measurements within a temporal window.
The main contributions of our paper are to 1) introduce partially blind
handovers, 2) employ machine learning to perform handover success predictions
from sub-6 GHz to mmWave frequencies, and 3) show that this machine learning
based algorithm combined with partially blind handovers can improve the
handover success rate in a realistic network setup of colocated cells.
Simulation results show improvement in handover success rates for our proposed
algorithm compared to standard handover algorithms.Comment: (c) 2018 IEEE. Personal use of this material is permitted. Permission
from IEEE must be obtained for all other uses, in any current or future
media, including reprinting/republishing this material for advertising or
promotional purposes, creating new collective works, for resale or
redistribution to servers or lists, or reuse of any copyrighted component of
this work in other work
Complex Block Floating-Point Format with Box Encoding For Wordlength Reduction in Communication Systems
We propose a new complex block floating-point format to reduce implementation
complexity. The new format achieves wordlength reduction by sharing an exponent
across the block of samples, and uses box encoding for the shared exponent to
reduce quantization error. Arithmetic operations are performed on blocks of
samples at time, which can also reduce implementation complexity. For a case
study of a baseband quadrature amplitude modulation (QAM) transmitter and
receiver, we quantify the tradeoffs in signal quality vs. implementation
complexity using the new approach to represent IQ samples. Signal quality is
measured using error vector magnitude (EVM) in the receiver, and implementation
complexity is measured in terms of arithmetic complexity as well as memory
allocation and memory input/output rates. The primary contributions of this
paper are (1) a complex block floating-point format with box encoding of the
shared exponent to reduce quantization error, (2) arithmetic operations using
the new complex block floating-point format, and (3) a QAM transceiver case
study to quantify signal quality vs. implementation complexity tradeoffs using
the new format and arithmetic operations.Comment: 6 pages, 9 figures, submitted to Asilomar Conference on Signals,
Systems, and Computers 201
A Portable Compton Gamma-Ray Camera Design
The purpose of this research is to investigate the angular resolution, efficiency, and energy resolution possible from a portable Compton camera gamma ray imaging system for possible use in the field of nuclear nonproliferation. The proposed device uses room temperature semiconductor and position sensitive scintillation detectors. The position and energy resolution (and their energy dependence) of a room temperature lithium drifted silicon (Si(Li)) detector and a position sensitive thallium -doped sodium iodide (NaI(Tl)) scintillation detector are investigated. The position and energy resolution of the position sensitive scintillation detector is also modeled computationally, and the results compared to measured data. An efficiency model is also presented. The angular resolution, efficiency, and energy resolution of the proposed system are calculated. The same computational methods are then applied to a hypothetical position sensitive Thallium doped cesium iodide (CsI(Tl)) scintillator. Based on the results, the angular resolution and energy resolution of a system employing this type of position sensitive detector coupled to the same room temperature Si(Li) detector is predicted
GNSS Signal Authentication via Power and Distortion Monitoring
We propose a simple low-cost technique that enables
civil Global Positioning System (GPS) receivers and other civil
global navigation satellite system (GNSS) receivers to reliably
detect carry-off spoofing and jamming. The technique, which
we call the Power-Distortion detector, classifies received signals
as interference-free, multipath-afflicted, spoofed, or jammed
according to observations of received power and correlatio
n
function distortion. It does not depend on external hardware or
a network connection and can be readily implemented on many
receivers via a firmware update. Crucially, the detector can with
high probability distinguish low-power spoofing from ordinary
multipath. In testing against over 25 high-quality empirical data
sets yielding over 900,000 separate detection tests, the detector
correctly alarms on all malicious spoofing or jamming attack
s
while maintaining a
<0.5% single-channel false alarm rate.Aerospace Engineering and Engineering Mechanic
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