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This paper presents outdoor wideband small-scale spatial fading and autocorrelation measurements and results in the 73 GHz millimeter-wave (mmWave) band conducted in downtown Brooklyn, New York. Both directional and omnidirectional receiver (RX) antennas are studied. Two pairs of transmitter (TX) and RX locations were tested with one line-of-sight (LOS) and one non-line-of-sight (NLOS) environment,...
This paper presents a novel no-reference objective algorithm for stereoscopic image quality assessment, called MUNIQUE, which is based on the estimation of both two-dimensional and stereoscopic features of images, namely local estimations of blockiness and blurriness and the disparity weighting technique. Applications of stereoscopic image and video quality assessment in surveillance systems are discussed...
For a solid evaluation of the performance of vehicular networks, a sound knowledge of the shadow fading characteristics and a suitable channel model to recreate those are essential. The fading variance as well as the correlation of the fading for a link between a base station and a mobile has been thoroughly discussed in the literature. This paper presents measurements of the fading correlation for...
This paper presents a performance model of the reception process in a wireless link with one antenna transmitter and a multiple-antenna maximum-ratio combining (MRC) receiver. The objective is to address the performance evaluation of multiple antenna systems enabled with adaptive modulation and coding (AMC). Two main assumptions are used: 1) Rayleigh fading correlated channels, and 2) imperfect (outdated)...
Assuming application of the received signal estimation method at an arbitrary remote location, we evaluate eavesdropping performance against the secret key agreement technique based on radio propagation characteristics. In the technique, key agreement is realized utilizing the locality of multipath fading. The locality can be broken by using the received signal estimation method and the possible range...
In this paper, we investigate the performance of the point-to-point multiple-input-multiple-output (MIMO) systems in the presence of a large but finite numbers of antennas at the transmitters and/or receivers. Considering the cases with and without hybrid automatic repeat request (HARQ) feedback, we determine the minimum numbers of the transmit/receive antennas which are required to satisfy different...
The ergodic capacity of spatially-correlated non-coherent multiple-input multiple-output channels is not known. In this paper upper and lower bounds are derived for this capacity at asymptotically high signal-to-noise ratios (SNRs). The bounds are accurate within an approximation error that decays as 1/SNR, and the gap between these bounds depends solely on the signalling dimensions and the condition...
In this paper, we examine the channel estimation in an amplify-and-forward (AF) one-way relay network (OWRN) under time selective flat fading scenario, where the distributed space-time coding (DSTC) is adopted at relay nodes. Our target is to estimate and track the individual channels of each relay hop instead of the composite channels. To reduce the number of the channel parameters to be estimated,...
This paper proposes a technique for intercepting the symmetric signals and uses the example of the widely used Triangular FM waveform as a case study, due to its importance. The interception process involves performing convolution of the received signal with itself. Due to the symmetric nature of the Triangular FM waveform, the output of this self-convolution procedure is the same as the autocorrelation...
Golay complementary code pairs have the advantage of being biphase, available at a variety of lengths as long as desired, with complete sidelobe cancellation. But, they have the disadvantage of requiring two frequencies/channels with the possibility of inexact sidelobe cancellation due to frequency selective fading. In this paper, the complementary code pair are transmitted at the same frequency band,...
Exploiting unique wireless channel characteristics like signal strength for secret key generation has been recently studied by researchers. These schemes are lightweight and suitable for resource constrained wearable devices. However, a major drawback of existing schemes is that the successive channel samples with small sampling interval will have high correlation in time. This reduces the entropy...
In this paper, we investigate the performance analysis of a multi-cell massive multiple-input multiple-output (MIMO) system that applies a conventional channel estimation technique, namely the linear Minimum Mean Square Error (LMMSE) over correlated Rician and correlated Nakagami-m fading channels. Based on this analysis, we find that increasing the line-of-sight (LOS) component can enhance the system...
The current policies of spectrum allocation leads to inefficient use of spectrum, making it scarce but the truth is, spectrum is not scarce but is underutilized. In today's era dynamic spectrum access is the need of the hour and cognitive radio is a novel technology which improves spectrum utilization. In this paper overview of cognitive radio along with spectrum sensing techniques is taken into account...
Secret key generation from the randomness provided by random channels is currently considered as one way to improve security in wireless communications at the physical layer level. However, the relation between the performance of SKG schemes and the characteristics of the radio channel has been moderately investigated. In this work, we evaluate the security performance through a simple channel model...
Shadowing from vehicles can degrade the performance of vehicle-to-vehicle (V2V) communication systems significantly. It is thus important to characterize and model the influence of common shadowing objects like cars properly. For multilink systems it is essential to model the joint effects on the different links. However, the multilink shadowing effects in V2V channels are not yet well understood...
This paper presents extensive propagation measurements conducted in a modern arched tunnel with 300 m and 500 m radii of curvature with horizontal polarizations at 920 MHz, 2400 MHz, and 5705 MHz, respectively. Based on the measurements, statistical metrics of propagation loss and shadow fading in all the measurement cases are extracted. Furthermore, for each of the large-scale fading parameters,...
In this paper, a cooperative satellite system consisting of two satellites is considered. After building the channel model, the channel capacity is analysed. Since the propagation time of the signal via different satellites is not equal, a scheme to handle the propagation time difference is proposed. Considering the various propagation time difference of different users, the scheme takes advantage...
Recent advancement in vehicular wireless applications is also a major contributing factor in spectrum scarcity. Cognitive radio technique can be applied to vehicular networks to fully exploit the underutilized licensed spectrum. Fast and reliable detection of primary user is the key component of cognitive radio networks. Energy detection (ED) based spectrum sensing is a viable choice for vehicular...
This work is devoted to the error rate and energy-efficiency analysis of regenerative cooperative networks in the presence of multipath fading and spatial correlation. To this end, exact analytic expressions are firstly derived for the symbol-error-rate of M-ary quadrature amplitude modulation in a dual-hop decode-and-forward relay system under spatially correlated Nakagami-m fading channels and maximum...
We study the propagation dynamics of a typical European forest by calculating and modeling shadowing fading correlations. This work relies on highly accurate propagation measurements that are able to capture the dynamics of such environment in detail. We also describe how such propagation measurements should be conducted to provide reliable results. These types of measurements are important for military,...
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