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In this paper, an enhanced differential carrier phase extraction method for carrier-suppressed wideband signal in CEI measurement is proposed. Based on Costas loop, after orthogonal transformation, low-pass filtering and phase detection, the differential carrier phase of the received signal of the two measuring stations can be obtained directly. It is more efficient comparing with the traditional...
In the channel blind estimation algorithm which exploits the first-order cyclostationarity in the received signal and performs circular deconvolution for Ultra Wide-Band (UWB) systems, there has a limitation that the duration of the channel must be less than the symbol duration. The problem can be effectively solved by using the channel shortening technique which compresses the length of the combined...
Inverse modeling of ground-based GNSS reflections has the potential to improve existing GNSS-R applications and lead to novel concepts for retrieving geophysical parameters around existing or deliberately built GNSS sites. As we will show in this paper, consistent, accurate and precise determination of sea-surface heights can be realized. Moreover, we demonstrate that it is possible to detect sea-ice...
Low Power Wide Area Networks (LPWAN) is a new solution for the Internet of Things (IoT). This type of networks already has several specific implementations like LoRa, Sigfox, Weightless, RPMA and others. Due to long wireless range, low power consumption and numerous nodes low speed overlay networks can be organized on top of LPWAN. Small pieces of data like text messages, low-quality photographs,...
Feedback delay can severely impact network performance in mobile network and the theoretical quantification of performance degradation has attracted much research interest recently. In this paper, we conduct coverage analysis of mobile ultra-dense networks (UDNs) where coordinated multipoint (CoMP) technology is adopted to enhance network performance and the available channel state information (CSI)...
The problem of increasing the efficiency of data transmission through a HF radio channel in the case of using passive sounding was studied. The paper presents the main characteristics of the stochastic radio channel with scattering (delay spread, Doppler spread and the signal-to-noise ratio) and communication modem, which have an impact on the efficiency of a communication system. Algorithm for estimating...
Secrecy capacity with time reversal technique is characterized and investigated for both specular and dense diffuse scattering radio channels. The characterization of secrecy capacity of specular radio channel is conducted for two clustered channels with 6 and 60 clusters that are composed of 120 and 1200 rays, respectively. Diffuse scattering channels are tested under different delay spread values...
5G wireless networks are expected to support new applications demanding ultra high reliability and ultra low latency, such as self-driving cars, industrial control, and real-time gaming. Such services are known as ultra-reliable and low-latency communications (URLLC) targeting at 99.999% transmission correctness within 1 ms delay bound. Current Long Term Evolution (LTE) system is far from supporting...
Coherent frequency conversion processes for frequency combs (FCs) are intensively studied as they inter alia enable the use of FCs for precision spectroscopy in the important mid-infrared (MIR) spectral region not covered by laser gain media. Difference frequency generation (DFG) is one promising approach for a simple and robust scheme to generate phase-stable MIR FCs. When used in a spectroscopy...
We study the physical-layer performance of a wideband multihop system in which a long chain of amplify-and-forward relays is used for routing orthogonal frequency division multiplexing (OFDM) symbols from a source to a destination. Especially, the symbols are modulated in the source and demodulated in the destination while the relays simply forward respective waveforms with scalar amplification. We...
In this paper, we address the need for motivating applications, such as mission critical industrial control and medical applications, to operate under the Ultra-Reliable Communication (URC) mode in the future 5th Generation (5G) cellular wireless networks, while also under strict Quality of Service (QoS) constraints such as ultra-low latency. Reliability has been shown to improve by using Hybrid Automatic...
A minimum mean square error estimation (MMSE) using a virtual pilot channel estimation scheme was proposed by our researchers for improving the error performance of the IEEE 802.11p. However, compared to the STA channel estimation scheme, the MMSE scheme cannot provide an acceptable error performance in a low SNR region. To alleviate this, we propose an adaptive channel estimation scheme, which selectively...
In this paper, we propose a low complexity Dynamic Hybrid Clustering (DHC) scheme for LTE-A networks employing Coordinated MultiPoint with Dynamic Point Selection (CoMP-DPS). Although CoMP-DPS is considered to be a simpler CoMP scheme, its simplicity allows us to define more efficient cell clustering procedures. Thus, DHC is able to provide backhaul load balancing for the eNBs while offering high...
This paper analyzes the effective capacity (EC) of delay constrained machine type communication (MTC) networks operating in the finite blocklength (FB) regime. First, we derive a closed-form mathematical approximation for the EC in Rayleigh block fading channels. We characterize the optimum error probability to maximize the concave EC function and study the effect of SINR variations for different...
Vehicles are the third fastest growing connected device type after smart phones and tablets. Also, automotive industry is interested to get more vehicles connected to the internet to improve traffic safety and efficiency. This creates a need for Vehicle-to-Everything (V2X) communications. In this work, the possibility of exploiting beamforming in LTE-V2X is considered. Singular value decomposition...
A two-path time-interleaved third-order ΣΔ modulator is presented. A domino-free solution moves a part of the required processing in the second path from the digital domain to the analog domain and relaxes the timing constraints of the second path ADC. Simulation results, achieved in a 65 nm CMOS technology, show that it is possible to achieve 90-dB SNR with a −6 dBFS input signal, a 4-bit quantizer,...
A clock generation system for a 1GS/s 8-bit subranging time-interleaved analog-to-digital converter (ADC) is introduced. General timing considerations for time-interleaved ADCs are reviewed prior to describing the design methodology for a prototype ADC. This hybrid ADC architecture contains four time-interleaved combined sample-and-hold and capacitive digital-to-analog converter (SHDAC) circuits as...
Existing indoor lighting systems consisting of incandescent bulbs and compact fluorescent lamps(CFLs) are being replaced by light emitting diodes(LEDs) at a much faster pace than envisaged. Such lighting systems are highly energy efficient, cost effective as well as environment-friendly. LEDs can also be used simultaneously for establishing indoor communication infrastructure known as visible light...
The increasing multimedia traffic and limited spectrum resource in Geosynchronous (GEO) satellite systems starve for an efficient Call Admission Control (CAC) scheme, which aims to provide acceptable Quality of Service (Qos) to massive users, however, the throughput may not be guaranteed. In order to maximize the total throughput of communication system, a dynamic CAC scheme, named Maximizing Throughput...
Internet of underground things (IOUT) is an emerging paradigm which consists of sensors and communication devices, partly or completely buried underground for real-time soil sensing and monitoring. In this paper, the performance of different modulation schemes in IOUT communications is studied through simulations and experiments. The spatial modularity of direct, lateral, and reflected components...
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