Proof of concept of a cavity backed slot antenna based on inverted microstrip gap ‎waveguide (IMGW) technology is presented. Since the antenna is operating based on the ‎first resonating mode of the cavity, it is more compact compared to the ordinary cavity ‎backed slot antennas in which the second cavity mode is used for radiation. Furthermore, ‎the proposed antenna element introduces lower lo...

Eavesdropping is a major concern in Cognitive Radio relay systems, due to the broadcast nature of these systems. Physical Layer Security (PLS) has been seen as a good alternative to enhance the secrecy performance of these networks. Based on the concept of perfect secrecy, PLS uses an information-theoretic approach to prevent secondary transmissions from malicious attacks. In this paper, the Se...

© 2009 Seung Hwan Lee et al. 481 This paper proposes a new multiuser scheduling algorithm that can simultaneously support a variety of different quality-of-service (QoS) user groups while satisfying fairness among users in the same QoS group in MIMO broadcast channels. Toward this goal, the proposed algorithm consists of two parts: a QoS-aware fair (QF) scheduling within a QoS group and an ante...

The eavesdropping attack is a serious security threat to a wireless sensor network (WSN) since the eavesdropping attack is a prerequisite for other attacks. Conventional WSNs consist of wireless nodes equipped with omnidirectional antennas, which broadcast radio signals in all directions and are consequently prone to the eavesdropping attacks. Different from omnidirectional antennas, directiona...

In this paper, a new antenna is presented which has an application in cellular telecommunication systems. The designed antenna works at the frequency range of 1900-2600 MHz which is able to cover 2G, 3G and 4G (LTE) services of the cellular telecommunication. In this paper, the micro-strip structure has been used to design the antenna. The shape of the patches is triangular where a peripheral r...

In this paper, a new method for designing an active dual-band dipole antenna is proposed. The operating frequencies of the proposed antenna are 150 and 450 MHz that are usually used in military applications. Using a series stub is the main idea in the proposed dual-band antenna, where it makes an independent resonance frequency higher than the main resonance frequency of a conventional dipole. ...

This paper describes a measurement acquisition method for aerospace systems that eliminates the need for sensors to have physical connection to a power source (i.e., no lead wires) or to data acquisition equipment. Furthermore, the method does not require the sensors to be in proximity to any form of acquisition hardware. Multiple sensors can be interrogated using this method. The sensors consi...

Realization of large capacity gains offered by multiple antenna systems depends upon the presence of channel state information (CSI) at the transmitter. However, very recently the overall impact of feedback on system capacity has been examined in order to highlight the hidden aspect of data rate loss due to feedback in general. In this paper, we extend the system model, called a duplex model th...

This paper presents a new design of a CPW-Fed multi bands planar antenna. This antenna can be integrated easily with passive and active elements. The proposed antenna is suitable to operate for GPS, PCS and WiMAX bands. Its entire area is 52.3x52.6mm2 and is employed on an FR-4 epoxy substrate and fed by a 50 Ohm coplanar line. The antenna parameters have been analyzed and optimized by using AD...