Abstract – Due to limited spectrum available
for use and steady expansion in the field of
wireless applications, it has become necessary
to organize all the applications in the same
available spectrum. To provide a way out to the
trouble of inefficient spectrum usage, Cognitive
Radios (CR) are considered as a promising
solution. A cognitive radio organization has
the ability to perform spectrum sensing and
transmission modifications by itself. A foremost
detector put in for Thomson’s Adaptive Multi-
Taper Spectrum Estimation (AMTSE) has been
discussed here. The detector has been employed
for adapting itself to the maximum and minimum
values. As a result, the detection threshold
adjusts itself according to the environmental
changes. The signal after being linearly precoded,
is divided into small segments and the
Discrete Prolate Spheroidal Sequences (DPSS)
are multiplied with it in order to get better
and smooth spectrum for detection. In case
of the existence of a PU exists, the technique
of interference cancellation has been applied
for cancelling the interference. Whereas,
when the PU is not using the spectrum band,
the Secondary User’s (SU) transmitter can
detect the Channel condition as a result to the
channel mutuality, granting the permission to
use the free spectrum band by some other user
who needs it. An idea to calculate the energy
and detecting the availability of spectrum has
been proposed, which leads to reduction in
False Alarm Rate P(fa) and rise in probability
of detection P(d).
Keywords— Adaptive Multi-Taper Spectrum
Estimator (AMTSE), Cognitive Radio (CR),
Discrete Prolate Spheroidal Sequences (DPSS),
Dynamic Spectrum Management, Linear
Precoding, Power Spectral Density (PSD).
- INTRODUCTION
With rapidly progressing advancementsdemands of wireless applications, Cognitive - Radios (CR) are considered as an assuring solution
- for raising the productivity of the available
- spectrum. CR is a type of communication which
- is done wirelessly, where a transceiver smartly
- detects which interface tracks are being used and
- which are vacant, and quickly moves into empty
- channels, thereby bypassing the occupied ones.
- This switching technique is called dynamic
- spectrum management. CR allows unlicensed
- SU to access the licensed spectrum band.