Multiuser multiple-input-multiple-output (MU-
MIMO) systems are known to be hindered by dimensionality
loss due to channel state information (CSI) acquisition overhead.
In this paper, we investigate user-scheduling in MU-MIMO
systems on account of CSI acquisition overhead, where a base
station dynamically acquires user channels to avoid choking the
system with CSI overhead.
This book addresses two aspects of network operation quality; namely, resource
management and fault management.
Network operation quality is among the functions to be fulfilled in order to offer
quality of service, QoS, to the end user. It is characterized by four parameters:
– packet loss;
– delay;
– jitter, or the variation of delay over time;
– availability.
Resource management employs mechanisms that enable the first three parameters
to be guaranteed or optimized. Fault management aims to ensure continuity of service.
At the macroscopic level of system layout, the most important issue is path loss. In the
older mobile radio systems that are limited by receiver noise, path loss determines SNR and
the maximum coverage area. In cellular systems, where the limiting factor is cochannel
interference, path loss determines the degree to which transmitters in different cells interfere
with each other, and therefore the minimum separation before channels can be reused.
his research aims at creating broadband tunable, fully integrated filters for the application of
cognitive radio and signal classification receivers. The approach under study is the N-path filter
technique which is capable of translating a baseband impedance to a reference frequency creating
a tunable filter. The traditional N-path filter suffers from fundamental architectural limitations,
namely : a trade-off between insertion loss and out-of-band rejection, reference clock feed-
through, and jammer power handling limitations. In the first approach, the fundamental trade-
off of the traditional N-path filter between insertion loss and out-of-band rejection is improved by
a transmission line (T-line) N-path filter technique.
Power Electronics is one of modern and key technologies in Electrical and
Electronics Engineering for green power, sustainable energy systems, and smart
grids. Especially, the transformation of existing electric power systems into smart
grids is currently a global trend. The gradual increase of distributed generators in
smart grids indicates a wide and important role for power electronic converters in
the electric power system, also with the increased use of power electronics devices
(nonlinear loads) and motor loadings, low cost, low-loss and high-performance
shunt current quality compensators are highly demanded by power customers to
solve current quality problems caused by those loadings.
Radio frequency identifi cation (RFID) technology is a wireless communication
technology that enables users to uniquely identify tagged objects or people.
RFID is rapidly becoming a cost-effective technology. This is in large part
due to the efforts of Wal-Mart and the Department of Defense (DoD) to
incorporate RFID technology into their supply chains. In 2003, with the aim
of enabling pallet-level tracking of inventory, Wal-Mart issued an RFID
mandate requiring its top suppliers to begin tagging pallets and cases, with
Electronic Product Code (EPC) labels. The DoD quickly followed suit and
issued the same mandate to its top 100 suppliers. This drive to incorporate
RFID technology into their supply chains is motivated by the increased ship-
ping, receiving and stocking effi ciency and the decreased costs of labor, storage,
and product loss that pallet-level visibility of inventory can offer.
PW2330 develops a high efficiency synchronous step down DC-DC converter capable of delivering3A output current. PW2330 operates over a wide input voltage range from 4.5V to 30V andintegrates main switch and synchronous switch with very low RDS(ON) to minimize the conductionloss. PW2330 adopts the proprietary instant PWM architecture to achieve fast transient responsesfor high step down applications and high efficiency at light loads. In addition, it operates atpseudo-constant frequency of 500kHz under continuous conduction mode to minimize the size ofinductor and capacitor
PW2205 develops a high efficiency synchronous step-down DC-DC converter capable of delivering5A output current. PW2205 operates over a wide input voltage range from 4.5V to 30V andintegrates main switch and synchronous switch with very low RDS(ON) to minimize the conductionloss.PW2205 adopts the instant PWM architecture to achieve fast transient responses for high step downapplications and high efficiency at light loads. In addition, it operates at pseudo-constant frequencyof 500kHz under continuous conduction mode to minimize the size of inductor and capacitor
The PW2202 is silicon N-channel Enhanced VDMOSFETs, is obtained by the self-aligned planarTechnology which reduce the conduction loss, improve switching performance and enhance theavalanche energy. The transistor can be used in various power switching circuit for system
