A stabilized photonic link has been developed that significantly simplifies X-band and Kaband signal transport for high-performance reference frequency distribution and antenna array applications. A cost-effective, integrated fiber-optic calibration technology provides long-term phase stability in the actual link used for broadband signal transport. This should directly benefit antenna array do...

—A MIMO backscatter RFID system consists of three operational ends: the query end (with M reader transmitting antennas), the tag end (with L tag antennas) and the receiving end (with N reader receiving antennas). Such an M × L × N setting in RFID can bring spatial diversity and has been studied for STC at the tag end. Current understanding of the query end is that it is only an energy provider ...

Wireless Sensor Networks (WSNs) are receiving an ever increasing attention because they are one of the most important technologies enabling the Internet of Things vision. Since nodes of these networks are battery-powered, energy efficiency represents one of the main design objectives. This goal can be primarily achieved through an optimization of the communication phase, which is the most power...

—A MIMO backscatter RFID system consists of three operational ends: the query end (with M reader transmitting antennas), the tag end (with L tag antennas) and the receiving end (with N reader receiving antennas). Such an M × L × N setting in RFID can bring spatial diversity and has been studied for STC at the tag end. Current understanding of the query end is that it is only an energy provider ...

With the advance of high speed laser technology, optical interaction with microwave circuits has become highly viable. Such interaction is advantageous as the fiber is low-loss, lightweight, and immune to electromagnetic interference. In this paper, interaction of direct-modulated and gain-switched optical links with active antenna phased array systems is demonstrated. In the direct-modulated o...

This article considers the exploitation of parasitic antenna arrays in multi-user (MU) wireless communication systems by using their adaptive beamforming capabilities in order to improve the average system throughput. The use of parasitic arrays and especially the electrically steerable passive array radiator (ESPAR) antennas enables the design of terminals with a single RF front-end and reduce...

This paper incorporates a comprehensive BER simulation study undertaken on the effectiveness of a Quasi Orthogonal Space time block code (QO-STBC) encoded DWT Based MIMO CDMA wireless communication system. The Code Division Multiple Access (CDMA) is a promising technique for high bit rate transmission in wireless communications systems. The QO-STBC encoded DWT Based MIMO CDMA system under prese...

Accurate and efficient channel estimation is important in multiple-antenna communication systems in order to effectively reduce the mutual interference among different transmitting antennas. For a nondispersive channel that is modeled by a single tap for each transmitting and receiving antenna pair, the well-known Hadamard sequences can be applied to estimate the channel coefficients. However, ...

Recently, there has been great interest in the development of advanced radar systems with phased arrays [1], [2]. In traditional multichannel radar array systems, the number of receivers should be equal to the number of receiving antennas, so the hardware expense and power consumption are very high [3]. A radar array system based on antenna switching is a promising substitute due to its lower c...

Microwave imaging techniques are prone to signal corruption from unwanted multipath signals. Near-field systems are especially vulnerable because signals can scatter and reflect from structural objects within or on the boundary of the imaging zone. These issues are further exacerbated when surface waves are generated with the potential of propagating along the transmitting and receiving antenna...