scholarly journals Signal processing for transmitted-reference ultra wideband system

2021 ◽  
Author(s):  
Alston L. Emmanuel ◽  
Xavier N. Fernando
Keyword(s):  
Wavelet Analysis ◽  
Performance Improvement ◽  
System Performance ◽  
Channel Model ◽  
Wireless Systems ◽  
Ultra Wideband ◽  
Ieee 802.11A ◽  
Transmitted Reference ◽  
Receiver Architecture ◽  
Notch Filtering

This thesis focuses on transmitted-reference ultra wideband (TR-UWB) systems coexistence with IEEE802.11a WLAN systems. TR-UWB systems can relax the difficult synchronization requirements and can provide a simple receiver architecture that gathers the energy from many resolvable multipath components. However, UWB TR systems are susceptible to interference which comes from other wireless systems. In this thesis, TR-UWB system performance is studied in the presence of strong IEEE 802.11a WLAN interference in both AWGN and IEEE channel model. In order to reduce both the effects of interference by and into UWB signals, we propose a new method in conjunction with a multi-carrier type transmission pulse using wavelet analysis and notch filtering. Using wavelet analysis, spectral density of the transmitted UWB signal around the interfering band is reduced by 60 dB lower than the peak. With the modified TR-UWB receiver, the TR-UWB system shows performance improvement in the presence of strong IEEE 8-2.11a interference in both AWGN and IEEE channel models. The proposed method can be used for the coexistence of different wireless systems with UWB system.

scholarly journals Signal processing for transmitted-reference ultra wideband system

2021 ◽  
Author(s):  
Alston L. Emmanuel ◽  
Xavier N. Fernando
Keyword(s):  
Wavelet Analysis ◽  
Performance Improvement ◽  
System Performance ◽  
Channel Model ◽  
Wireless Systems ◽  
Ultra Wideband ◽  
Ieee 802.11A ◽  
Transmitted Reference ◽  
Receiver Architecture ◽  
Notch Filtering

This thesis focuses on transmitted-reference ultra wideband (TR-UWB) systems coexistence with IEEE802.11a WLAN systems. TR-UWB systems can relax the difficult synchronization requirements and can provide a simple receiver architecture that gathers the energy from many resolvable multipath components. However, UWB TR systems are susceptible to interference which comes from other wireless systems. In this thesis, TR-UWB system performance is studied in the presence of strong IEEE 802.11a WLAN interference in both AWGN and IEEE channel model. In order to reduce both the effects of interference by and into UWB signals, we propose a new method in conjunction with a multi-carrier type transmission pulse using wavelet analysis and notch filtering. Using wavelet analysis, spectral density of the transmitted UWB signal around the interfering band is reduced by 60 dB lower than the peak. With the modified TR-UWB receiver, the TR-UWB system shows performance improvement in the presence of strong IEEE 8-2.11a interference in both AWGN and IEEE channel models. The proposed method can be used for the coexistence of different wireless systems with UWB system.

Mitigation of wideband interference on UWB-IR transmission using multi-carrier templates

2009 ◽  
Vol 1 (1) ◽  
pp. 73-81 ◽  
Author(s):  
Madan Kumar Lakshmanan ◽  
Homayoun Nikookar
Keyword(s):  
Interference Mitigation ◽  
Channel Model ◽  
Path Loss ◽  
Wireless Systems ◽  
Ultra Wideband ◽  
Propagation Channel ◽  
Ieee 802.11A ◽  
Wideband Interference ◽  
Ir Transmission ◽  
Uwb Communication

Ultra wideband (UWB) wireless systems are highly susceptible to interference from other services. To reduce the effect of interference from co-existing sources such as the WLAN standard IEEE 802.11a on UWB Communication, the construction of a modified template waveform using multi-carrier sinusoids is proposed in Ohno and Ikegami (2003), Ohno et al. (2004), Ohno and Ikegami (2006), and Lakshmanan and Nikookar (2007). However, the work in Ohno and Ikegami (2003), Ohno et al. (2004), Ohno and Ikegami (2006), and Lakshmanan and Nikookar (2007) considers a free space propagation channel model with no treatment of the frequency dependence of the path loss. In this paper, we broaden the study by taking into consideration a frequency-dependent path loss environment. The novelty of the work is in the investigation of the effect of frequency dependency of the path loss on the performance of interference mitigation schemes.

MIMO Systems in a Composite Fading and Generalized Noise Scenario: A Review

2020 ◽  
Vol 14 ◽  
Author(s):  
Keerti Tiwari
Keyword(s):  
System Performance ◽  
Performance Enhancement ◽  
Channel Model ◽  
Mimo Systems ◽  
Mimo System ◽  
Spatial Diversity ◽  
Spatial Multiplexing ◽  
Channel Models ◽  
Efficient System ◽  
Composite Channel

: Multiple-input multiple-output (MIMO) systems have been endorsed to enable future wireless communication requirements. The efficient system designing appeals an appropriate channel model, that considers all the dominating effects of wireless environment. Therefore, some complex or less analytically acquiescent composite channel models have been proposed typically for single-input single-output (SISO) systems. These models are explicitly employed for mobile applications, though, we need a specific study of a model for MIMO system which can deal with radar clutters and different indoor/outdoor and mobile communication environments. Subsequently, the performance enhancement of MIMO system is also required in such scenario. The system performance enhancement can be examined by low error rate and high capacity using spatial diversity and spatial multiplexing respectively. Furthermore, for a more feasible and practical system modeling, we require a generalized noise model along with a composite channel model. Thus, all the patents related to MIMO channel models are revised to achieve the near optimal system performance in real world scenario. This review paper offers the methods to improve MIMO system performance in less and severe fading as well as shadowing environment and focused on a composite Weibull-gamma fading model. The development is the collective effects of selecting the appropriate channel models, spatial multiplexing/detection and spatial diversity techniques both at the transmitter and the receivers in the presence of arbitrary noise.

scholarly journals Complex System Governance as a Framework for Asset Management

2021 ◽  
Vol 13 (15) ◽  
pp. 8502
Author(s):  
Polinpapilinho F. Katina ◽  
James C. Pyne ◽  
Charles B. Keating ◽  
Dragan Komljenovic
Keyword(s):  
Complex System ◽  
Performance Improvement ◽  
Asset Management ◽  
System Performance ◽  
Future Research ◽  
Complex Organizations ◽  
Potential Relationship ◽  
Structured Approach

Complex system governance (CSG) is an emerging field encompassing a framework for system performance improvement through the purposeful design, execution, and evolution of essential metasystem functions. The goal of this study was to understand how the domain of asset management (AsM) can leverage the capabilities of CSG. AsM emerged from engineering as a structured approach to organizing complex organizations to realize the value of assets while balancing performance, risks, costs, and other opportunities. However, there remains a scarcity of literature discussing the potential relationship between AsM and CSG. To initiate the closure of this gap, this research reviews the basics of AsM and the methods associated with realizing the value of assets. Then, the basics of CSG are provided along with how CSG might be leveraged to support AsM. We conclude the research with the implications for AsM and suggested future research.

BER performance analysis of FSO using hybrid-SIM technique with APD receiver over weak and strong turbulence channels

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Rajat Kumar Giri
Keyword(s):  
Performance Improvement ◽  
System Performance ◽  
Avalanche Photodiode ◽  
Free Space Optical ◽  
Error Performance ◽  
Strong Turbulence ◽  
Meijer G Function ◽  
Hermite Approximation ◽  
Ber Performance ◽  
Better Than

Abstract In this paper, a hybrid-subcarrier-intensity-modulation (hybrid-SIM) technique for the performance improvement of free-space-optical (FSO) communication system has been proposed. Subsequently, for further error performance improvement, avalanche photodiode (APD) based receiver is used in the proposed system. The system performance is analyzed at various atmospheric turbulence levels over weak and strong turbulence channels. The bit error rate (BER) is theoretically derived using Gauss–Hermite approximation and Meijer-G function and it is simulated in the MATLAB environment. The simulation result shows that the BER performance of hybrid-SIM is better than BPSK-SIM technique irrespective of the channel types and also the significant BER performance improvement is observed by APD receiver.

Angle and polarization-independent miniaturized UWB FSS design

2021 ◽  
pp. 1-9
Author(s):  
Yanning Yuan ◽  
Yuchen Zhao ◽  
Xiaoli Xi
Keyword(s):  
Design Method ◽  
Incident Angle ◽  
Stop Band ◽  
Single Layer ◽  
Wireless Systems ◽  
Frequency Selective Surface ◽  
Ultra Wideband ◽  
Band Frequency ◽  
Gain Enhancement ◽  
Polarization Independent

Abstract A single-layer ultra-wideband (UWB) stop-band frequency selective surface (FSS) has several advantages in wireless systems, including a simple design, low debugging complexity, and an appropriate thickness. This study proposes a miniaturized UWB stop-band FSS design. The proposed FSS structure consists of a square-loop and metalized vias that are arranged on a single layer substrate; it has an excellent angle and polarization-independent characteristics. At an incident angle of 60°, the polarization response frequencies of the transverse electric and magnetic modes only shifted by 0.003 f0 and 0.007 f0, respectively. The equivalent circuit models of the square-loop and metallized vias structure are analysed and the accuracy of the calculation is evaluated by comparing the electromagnetic simulation. The 20 × 20 array constitutes an FSS reflector with a unit size of 4.2 mm × 4.2 mm (less than one-twentieth of the wavelength of 3 GHz), which realizes an UWB quasi-constant gain enhancement (in-band flatness is <0.5 dB). Finally, the simulation results were verified through sample processing and measurement; consistent results were obtained. The FSS miniaturization design method proposed in this study could be applied to the design of passband FSS (complementary structure), antennas and filters, among other applications.

A window detection technique with adjustable threshold for transmitted reference receivers

2013 ◽  
Vol 3 (1) ◽  
Author(s):  
Apratim Roy ◽  
A. Rashid
Keyword(s):  
Input Data ◽  
Cmos Technology ◽  
Ultra Wideband ◽  
Power Requirement ◽  
The Core ◽  
Transmitted Reference ◽  
Detection Circuit ◽  
Detection Window ◽  
Improved Performance ◽  
Decision Circuit

AbstractThis paper presents a threshold decision circuit with an adjustable detection window designed in a 90-nm IBM CMOS technology. Together with an RF mixer, the decision Section realizes the circuit implementation of the back-end of a transmitted reference ultra wideband receiver, which is yet to be reported in literature. The proposed circuit is built on a differential amplifier core and avoids the use of integrator and sampling blocks, which reduces the device burden necessary for the architecture. Moreover, the detection window threshold of the design can be regulated by three independent factors defined by the circuit elements. The circuit is tested at an input data rate of 0.1∼2.0 Gbps and the core decision section consumes 9.14 mW from a 1.2-V bias supply (with a maximum capacity/Pdc ratio of 218.8 GHz/W). When compared against other reported decision blocks, the proposed detection circuit shows improved performance in terms of capacity and power requirement.

Sign in / Sign up

Export Citation Format

Share Document