A compact dual-band antenna made of high dielectric constant substrate is studied. Embedding a higher dielectric cylindrical inside the substrate host cylindrical enhances the dual-band behaviour. The first part displays the characteristics of single CRDA as return loss, bandwidth and radiation pattern, then, the second part describes the aim of using an antenna, composed by the arrangement of ...

In this paper, a dual frequency phase sensitive demodulation (PSD) technique is suggested to measure electrode voltages in electrical impedance tomography. The simulation results obtained by the dual frequency PSD are compared with the single frequency PSD in terms of accuracy on a simple phantom.

Single frequency laser sources are desired in many applications. Various architectures for achieving high power single frequency fiber laser outputs have been investigated and demonstrated. Axial gain apodization can affect the lasing threshold and spectral modal discrimination of DFB lasers. Modeling results show that if properly tailored, the lasing threshold can be reduced by 21% without sac...

This paper is to study Qiyang double contours from acoustic and perceptual perspective. A noteworthy sandhi pattern and the perception experiment results indicate that Qiyang qushengs (departing tones) are underlying double contours, i.e. 4232(yinqu) and 2142(yangqu), because their falling tails are phonologically active and lexically encoded. This seriously challenges the current tone geometri...

We address the peak-to-average power ratio (PAPR) of transmission signals in OFDM and consider the performance of tone reservation for reduction of the PAPR. Tone reservation is unique among methods for reducing PAPR, because it does not affect information bearing coefficients and involves no additional coordination of transmitter and receiver. It is shown that if the OFDM system always satisfi...

Direct sequence (DS) and Multi-carrier (MC) code division multiple access (CDMA) are competing schemes for wireless multiple access systems. They have been studied and compared by many researchers. Time and frequency domains have long been used to represent linear systems in dual forms. In this paper it is shown, using time-frequency duality, that DS and MC can be considered dual CDMA systems o...

Abstract: The purpose of this paper was to design and implementation a single feed, dual frequency ( L1, L2) patch antenna for the Global Positioning System (GPS). The results from the simulation and measurement for this antenna is presented, compared, and used as part of the validation process for the dual frequency, right hand circularly polarized patch antenna designed for GPS L1, L2 operati...