1,614 research outputs found
An Overview of Broadband communication over Power Lines
Broadband over power lines are Systems for carrying
data on conductors used for electric power
transmission. Power line communication technologies
can be used for different applications ranging from
home automation to internet access.
With the spread of broadband technologies in the last
few years, there are yet significant areas in the world
that do not have access to high speed internet, as
compared with the few internet service providers in
existence, the additive expenditures of laying cables
and building necessary infrastructure to provide DSL
in many areas most especially rural areas is too great.
But if broadband is served through power lines
considering the fact that it exist all over the country,
there will be no need to build new infrastructure.
Therefore, anywhere there is electricity, there could
also be broadband.
Broadband over Power line is designed to offer an
alternative means to provide high speed internet
access, voice over Internet protocol (VOIP) and other
broadband services, using medium and low voltage
lines to reach customers and businesses by combining
the principle of wireless networking, modems and
Radio. Researchers and developers have created ways
to transmit data over power lines into homes at
speeds between 500kilobits and 3 megabits per
second which is equivalent to the cable DSL (Digital
Subscriber Line) and this is achieved by modifying
the present power grids with specialized equipments.
With this knowledge, the broadband power line
developers could partner with power companies and
Internet service providers to bring broadband to
everyone with access to electricity
An enhanced OFDM light weight physical layer encryption scheme
The broadcast nature of wireless networks makes them susceptible to attacks by eavesdroppers than wired networks. Any untrusted node can eavesdrop on the medium, listen to transmissions and obtain sensitive information within the wireless network. In this paper, we propose a new mechanism which combines the advantages of two techniques namely iJam and OFDM phase encryption. Our modified mechanism makes iJam more bandwidth efficient by using Alamouti scheme to take advantage of the repetition inherent in its implementation. The adversary model is extended to the active adversary case, which has not been done in the original work of iJam and OFDM phase encryption. We propose, through a max min optimization model, a framework that maximizes the secrecy rate by means of a friendly jammer. We formulate a Zero-Sum game that captures the strategic decision making between the transmitter receiver pair and the adversary. We apply the fictitious play (FP) algorithm to reach the Nash equilibria (NE) of the game. Our simulation results show a significant improvement in terms of the ability of the eavesdropper to benefit from the received information over the traditional schemes, i.e. iJam or OFDM phase encryption
Design of an OFDM Physical Layer Encryption Scheme
This paper presents a new encryption scheme implemented at the physical layer of wireless networks employing orthogonal frequency-division multiplexing (OFDM). The new scheme obfuscates the subcarriers by randomly reserving several subcarriers for dummy data and resequences the training symbol by a new secure sequence. Subcarrier obfuscation renders the OFDM transmission more secure and random, whereas training symbol resequencing protects the entire physical layer packet but does not affect the normal functions of synchronization and channel estimation of legitimate users while preventing eavesdroppers from performing these functions. The security analysis shows that the system is robust to various attacks by analyzing the search space using an exhaustive key search. Our scheme is shown to perform better in terms of search space, key rate, and complexity in comparison with other OFDM physical layer encryption schemes. The scheme offers options for users to customize the security level and the key rate according to the hardware resource. Its low complexity nature also makes the scheme suitable for resource-limited devices. Details of practical design considerations are highlighted by applying the approach to an IEEE 802.11 OFDM system case study
Securing Wireless Communications of the Internet of Things from the Physical Layer, An Overview
The security of the Internet of Things (IoT) is receiving considerable
interest as the low power constraints and complexity features of many IoT
devices are limiting the use of conventional cryptographic techniques. This
article provides an overview of recent research efforts on alternative
approaches for securing IoT wireless communications at the physical layer,
specifically the key topics of key generation and physical layer encryption.
These schemes can be implemented and are lightweight, and thus offer practical
solutions for providing effective IoT wireless security. Future research to
make IoT-based physical layer security more robust and pervasive is also
covered
Power Line Communication Technologies: Modeling and Simulation of PRIME Physical Layer
Power Line Communications is a relatively new
area of telecommunication. PLC employs full duplex methods
for transmitting data over power lines as medium of
transmission of electrical signals over a grid. PLC technologies
are used in advanced meter reading, home automation and
Public street lighting. Several PLC technologies classified
based on the operational frequency range, are explored in this
paper. PRIME is a new NBPLC system, which uses OFDM in
its physical layer, for power line communication in the last
mile. This work also focused on PRIMEâs physical
specifications, which was modeled in MATLAB/SIMULINK.
In this paper, the performance of PRIME when its data is
modulated using DQPSK and 4-QAM in four (4) channel
models is shown.
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