1,364 research outputs found
Cyclic-Coded Integer-Forcing Equalization
A discrete-time intersymbol interference channel with additive Gaussian noise
is considered, where only the receiver has knowledge of the channel impulse
response. An approach for combining decision-feedback equalization with channel
coding is proposed, where decoding precedes the removal of intersymbol
interference. This is accomplished by combining the recently proposed
integer-forcing equalization approach with cyclic block codes. The channel
impulse response is linearly equalized to an integer-valued response. This is
then utilized by leveraging the property that a cyclic code is closed under
(cyclic) integer-valued convolution. Explicit bounds on the performance of the
proposed scheme are also derived
Molecular Signal Modeling of a Partially Counting Absorbing Spherical Receiver
To communicate at the nanoscale, researchers have proposed molecular
communication as an energy-efficient solution. The drawback to this solution is
that the histogram of the molecules' hitting times, which constitute the
molecular signal at the receiver, has a heavy tail. Reducing the effects of
this heavy tail, inter-symbol interference (ISI), has been the focus of most
prior research. In this paper, a novel way of decreasing the ISI by defining a
counting region on the spherical receiver's surface facing towards the
transmitter node is proposed. The beneficial effect comes from the fact that
the molecules received from the back lobe of the receiver are more likely to be
coming through longer paths that contribute to ISI. In order to justify this
idea, the joint distribution of the arrival molecules with respect to angle and
time is derived. Using this distribution, the channel model function is
approximated for the proposed system, i.e., the partially counting absorbing
spherical receiver. After validating the channel model function, the
characteristics of the molecular signal are investigated and improved
performance is presented. Moreover, the optimal counting region in terms of bit
error rate is found analytically.Comment: submitted to Transactions on Communication
Non-coherent Massive SIMO Systems in ISI Channels: Constellation Design and Performance Analysis
A massive single-input multiple-output (SIMO) system with a single transmit
antenna and a large number of receive antennas in intersymbol interference
(ISI) channels is considered. Contrast to existing energy detection (ED)-based
non-coherent receiver where conventional pulse amplitude modulation (PAM) is
employed, we propose a constellation design which minimizes the symbol-error
rate (SER) with the knowledge of channel statistics. To make a comparison, we
derive the SERs of the ED-based receiver with both the proposed constellation
and PAM, namely and . Specifically, asymptotic
behaviors of the SER in regimes of a large number of receive antennas and high
signal-to-noise ratio (SNR) are investigated. Analytical results demonstrate
that the logarithms of both and decrease
approximately linearly with the number of receive antennas, while
degrades faster. It is also shown that the proposed design is of less cost,
because compared with PAM, less antennas are required to achieve the same error
rate
The CMEA system of trade and payments : the legacy and the aftermath of its termination
This paper describes the Council for Mutual Economic Assistance (CMEA) system of trade and payment (the"CMEA regime") and considers how the transition from traditional socialism to a market economy is linked to changes in the mechanism for international transactions. The paper begins with a brief history of the CMEA and a description of its organizational structure, institutional principles, and reform efforts. It then provides a brief statistical overview of the relative importance of CMEA trade to its members. The paper sets out the traditional"institutional model"of the CMEA regime, discusses its defects, and briefly evaluates the CMEA regime. After a description of the events surrounding the CMEA's demise in 1990, the paper concludes with the author's conjectures about the consequences of that demise.Environmental Economics&Policies,Economic Theory&Research,TF054105-DONOR FUNDED OPERATION ADMINISTRATION FEE INCOME AND EXPENSE ACCOUNT,Trade Policy,Markets and Market Access
- …