Penn State College of Communications

About: Penn State College of Communications is a based out in . It is known for research contribution in the topics: Relay & Cognitive radio. The organization has 2106 authors who have published 2119 publications receiving 24693 citations.

Energy-efficient optimization for physical layer security in large-scale random CRNs

Abstract: Energy-efficiency, high data rates and secure communications are essential requirements of the future wireless networks. In this paper, we develop a framework to study the energy efficiency for enhancing physical layer security (PLS) in large-scale random cognitive radio networks (CRNs) considering the node spatial distribution, wireless propagation medium and aggregate network interference. Using stochastic geometry, we model the large-scale random secure CRN, and analyze the connection outage probability (COP) and the secrecy outage probability (SOP) of typical secondary link. Based on the results, we introduce the secrecy energy efficiency (SEE) to character the energy efficiency for enhancing the physical layer security of secondary network. Furthermore, we jointly optimizing the medium access probability (MAP) and transmit power of secondary transmitters (STs) to maximize the secrecy energy efficiency. Finally, numerical results are conducted to evaluate the SEE and examine the effect of system parameters.

AMC-Based Planar Antenna with Low-Profile and Broad CP Beamwidth

Abstract: A low-profile circularly-polarized (CP) antenna with broad axialratio (AR) beamwidth is presented by loading with artificial magnetic conductor (AMC). The antenna consists of a couple of modified dipoles with four crossed symmetrical fan-shaped arms and a magneto-electric (ME) dipole equipped to broaden AR beamwidth. One AMC consists of 5 × 5 units is integrated to reduce the backward scattering wave and simultaneously ensures a low profile. The measured results of one fabricated type reveal that the AMC-integrated antenna accomplishes a wide 3-dB AR beamwidth (>135°) and exhibits a low-profile property with the height of 0.054λ0, which can be applied in the BeiDou Satellite System (BDS).

High-power VHF tunable filters with high selectivity

Abstract: A tunable helical bandpass filter with high selectivity designed for 30-88 MHz operation is presented. The two-pole tunable filter is discretely tuned by connecting PIN switched capacitor banks at the terminal ends of the helix. The filter schematic provides two finite transmission zeros located in the lower and upper stopbands, respectively. The experimental filter has an insertion loss between 1.65 and 2.75 dB with its return loss better than 13 dB. The 3-dB fractional bandwidth of the filter is 3.3%-3.7% and the shape factor (BW 30 dB /BW 3 dB ) is smaller than 5.5 over the entire tuning range. The input power handling capability is greater than 45 dBm. The measured results show good agreement with the simulated ones.