A system simulation environment in Matlab/Simulink of RFID is constructed in this paper.
Special attention is emphasized on the analog/RF circuit.Negative effects are concerned in the system
model,such as phase noise of the local oscillator,TX-RX coupling,reflection of the environment,
AWGN noise,DC offset,I/Q mismatch,etc.Performance of the whole system can be evaluated by
changing the coding method,parameters of building blocks,and operation distance.Finally,some
simulation results are presented in this paper.
Carrier-phase synchronization can be approached in a
general manner by estimating the multiplicative distortion (MD) to which
a baseband received signal in an RF or coherent optical transmission
system is subjected. This paper presents a unified modeling and
estimation of the MD in finite-alphabet digital communication systems. A
simple form of MD is the camer phase exp GO) which has to be estimated
and compensated for in a coherent receiver. A more general case with
fading must, however, allow for amplitude as well as phase variations of
the MD.
We assume a state-variable model for the MD and generally obtain a
nonlinear estimation problem with additional randomly-varying system
parameters such as received signal power, frequency offset, and Doppler
spread. An extended Kalman filter is then applied as a near-optimal
solution to the adaptive MD and channel parameter estimation problem.
Examples are given to show the use and some advantages of this scheme.
