Enhancing sensitivity for emitter geolocation

2012 ◽  
Vol 4 (2) ◽  
pp. 129-135 ◽  
Author(s):  
Göran Tengstrand ◽  
Peter Hultman ◽  
Jean-François Grandin ◽  
Dario Benvenuti ◽  
Börje Andersson ◽  
...  
Keyword(s):  
Signal Processing ◽  
High Accuracy ◽  
Search Pattern ◽  
Low Latency ◽  
Time Of Arrival ◽  
Antenna Gain ◽  
Sufficient Data ◽  
Angle Of Arrival ◽  
Data Link ◽  
Very High

Angle of arrival (AOA), time of arrival (TOA), and frequency of arrival (FOA) can be measured for a signal from multiple platforms. By combining such measurements it is possible to obtain high-accuracy emitter position estimates. This requires a data link with low latency and sufficient data-rate, and synchronization of the platforms in space, time, and search pattern. Typically several of the platforms will have to make their measurements in the radar sidelobes that require very high receiver sensitivity. This paper focuses on discussing how the sensitivity can be improved using antenna gain or signal processing.

INTERFERER REJECTION IMPROVED BY NOISE IN ULTRA-WIDEBAND TELECOMMUNICATIONS

2006 ◽  
Vol 06 (03) ◽  
pp. L317-L328 ◽  
Author(s):  
JOCELYN FIORINA ◽  
DAVID ROUSSEAU ◽  
FRANÇOIS CHAPEAU-BLONDEAU
Keyword(s):  
Signal Processing ◽  
Gaussian Noise ◽  
Multiple Access ◽  
High Speed ◽  
High Accuracy ◽  
Ultra Wideband ◽  
Positioning Systems ◽  
Very High ◽  
Low Rate ◽  
External Impulse

Ultra-wideband technology uses baseband transmission of low-power ultra-short information-bearing impulses, and represents a promising approach for very-high speed wireless communications with multiple access, as well as for low-rate high-accuracy positioning systems. The first demonstrations of the huge potential of ultra-wideband were based on hypotheses of perfect power control and multiuser interferences modeled as white Gaussian noise. Here, by explicitly modeling the interference with an external impulse signal, we demonstrate the possibility of improving the rejection of the interferer thanks to a constructive action of the noise. This is interpreted as a novel instance of the phenomenon of stochastic resonance or improvement by noise in signal processing.

scholarly journals Stellar magnetic imaging from spectropolarimetric data

1996 ◽  
Vol 176 ◽  
pp. 53-60 ◽  
Author(s):  
J.-F. Donati
Keyword(s):  
Small Amplitude ◽  
High Accuracy ◽  
Spectral Lines ◽  
New Method ◽  
Doppler Imaging ◽  
Magnetic Imaging ◽  
Active Stars ◽  
Surface Fields ◽  
Very High

In this paper, I will review the capabilities of magnetic imaging (also called Zeeman-Doppler imaging) to reconstruct spot distributions of surface fields from sets of rotationnally modulated Zeeman signatures in circularly polarised spectral lines. I will then outline a new method to measure small amplitude magnetic signals (typically 0.1% for cool active stars) with very high accuracy. Finally, I will present and comment new magnetic images reconstructed from data collected in 1993 December at the Anglo-Australian Telescope (AAT).

Hole Accuracy during Deep Hole Drilling for Hydraulic Cylinder Application

2014 ◽  
Vol 984-985 ◽  
pp. 67-72 ◽  
Author(s):  
R. Clifford Benjamin Raj ◽  
B. Anand Ronald ◽  
A. Velayudham ◽  
Prasmit Kumar Nayak
Keyword(s):  
Feed Rate ◽  
Drill Hole ◽  
Hydraulic Cylinder ◽  
High Accuracy ◽  
Diameter Ratio ◽  
Hole Drilling ◽  
Deep Hole ◽  
Deep Hole Drilling ◽  
Very High ◽  
Continuous Chip

Deep-hole drilling is a process in which the hole length will be very high when compared to diameter of the drill hole (i.e. length to diameter ratio will be greater than 5). Drilling a deep hole with very high accuracy is difficult process. The current project is about the production of deep hole with the aim to produce a chip which is not a continuous chip and also not a powdery chip. These conditions can be attained by varying the spindle speed and the tool feed rate.

Cost Effective Swath Bathymetry

2001 ◽  
Vol 35 (4) ◽  
pp. 33-45 ◽  
Author(s):  
Peter Hogarth
Keyword(s):  
Processing Time ◽  
Cost Effective ◽  
High Accuracy ◽  
High Coverage ◽  
Swath Bathymetry ◽  
World Survey ◽  
Set Up ◽  
Very High ◽  
Harbor Area ◽  
Wide Swath

Between 23rd and 25th July 2001 GeoSwath, a high specification shallow water wide swath bathymetry system, was used to survey the entire Portsmouth NH Harbor area. This paper deals with the results of this survey, illustrating the potential for significant reductions in the high costs, which have prevented widespread proliferation of Swath Bathymetry systems to date. Data, including a complete DTM gridded to 1 m resolution, will be presented and discussed in detail. These results show that the system is very easy to set up and use, requires greatly reduced boat and processing time, whilst offering high accuracy and very high coverage and resolution when used in a real-world survey of a dynamic harbor environment.

M1212 Celiac Disease Serology with Very High Accuracy May Obviate Diagnostic Intestinal Biopsy in Different Clinical Scenarios

2008 ◽  
Vol 134 (4) ◽  
pp. A-362
Author(s):  
Emilia Sugai ◽  
María Laura Moreno ◽  
Hui Jer Hwang ◽  
Adriana Crivelli ◽  
Fabio Nachman ◽  
...  
Keyword(s):  
Celiac Disease ◽  
High Accuracy ◽  
Intestinal Biopsy ◽  
Clinical Scenarios ◽  
Very High

A high accuracy linear rate meter

1975 ◽  
Vol 39 (2) ◽  
pp. 327-330
Author(s):  
C. R. Wyss
Keyword(s):  
Circuit Design ◽  
Digital Circuits ◽  
Analog Computer ◽  
High Accuracy ◽  
Digital Display ◽  
Instantaneous Rate ◽  
Linear Rate ◽  
Very High ◽  
Design Techniques

By implementing analog computer techniques using digital circuits, an instantaneous rate meter was built with approximately 100 times the accuracy of commercially available rate meters. The circuit is accurate to within +/- 0.2 events/min over a range of rates of 0.2–900 epm. Modifications can be made to provide a digital display of rate. The circuit design techniques used in developing the rate meter may be used to generate a wide variety of functions of time with very high accuracy.

scholarly journals Non-Line-of-Sight Error Mitigation in Wireless Communication Systems

2011 ◽  
Vol 1 ◽  
pp. 173-177
Author(s):  
Szu Lin Su ◽  
Yi Wen Su ◽  
Ho Nien Shou ◽  
Chien Sheng Chen
Keyword(s):  
Communication Systems ◽  
Hybrid Methods ◽  
Mobile Station ◽  
Base Stations ◽  
Superior Performance ◽  
Line Of Sight ◽  
Time Of Arrival ◽  
Angle Of Arrival ◽  
Error Statistics ◽  
Non Line Of Sight

When there is non-line-of-sight (NLOS) path between the mobile station (MS) and base stations (BSs), it is possible to integrate many kinds of measurements to achieve more accurate measurements of the MS location. This paper proposed hybrid methods that utilize time of arrival (TOA) at five BSs and angle of arrival (AOA) information at the serving BS to determine the MS location in NLOS environments. The methods mitigate the NLOS effect simply by the weighted sum of the intersections between five TOA circles and the AOA line without requiring priori knowledge of NLOS error statistics. Simulation results show that the proposed methods always give superior performance than Taylor series algorithm (TSA) and the hybrid lines of position algorithm (HLOP).

Discrete differential operators for periodic and two-periodic time functions

2019 ◽  
Vol 38 (1) ◽  
pp. 325-347 ◽  
Author(s):  
Tadeusz Sobczyk ◽  
Michał Radzik ◽  
Natalia Radwan-Pragłowska
Keyword(s):  
Differential Operators ◽  
High Accuracy ◽  
Large Set ◽  
Periodic Functions ◽  
Content Type ◽  
Second Derivatives ◽  
Non Linear ◽  
Discrete Operators ◽  
Linear Differential ◽  
Very High

Purpose To identify the properties of novel discrete differential operators of the first- and the second-order for periodic and two-periodic time functions. Design/methodology/approach The development of relations between the values of first and second derivatives of periodic and two-periodic functions, as well as the values of the functions themselves for a set of time instants. Numerical tests of discrete operators for selected periodic and two-periodic functions. Findings Novel discrete differential operators for periodic and two-periodic time functions determining their first and the second derivatives at very high accuracy basing on relatively low number of points per highest harmonic. Research limitations/implications Reduce the complexity of creation difference equations for ordinary non-linear differential equations used to find periodic or two-periodic solutions, when they exist. Practical implications Application to steady-state analysis of non-linear dynamic systems for solutions predicted as periodic or two-periodic in time. Originality/value Identify novel discrete differential operators for periodic and two-periodic time functions engaging a large set of time instants that determine the first and second derivatives with very high accuracy.

scholarly journals On Ultra-Reliable Low Latency Multipath TCP For Connected Autonomous Vehicles

2021 ◽  
Author(s):  
Shiva Raj Pokhrel ◽  
Neeraj Kumar ◽  
Anwar Walid
Keyword(s):  
Autonomous Vehicles ◽  
High Speed ◽  
Data Communication ◽  
Low Latency ◽  
Data Traffic ◽  
Mathematical Study ◽  
Multipath Tcp ◽  
Multiple Network ◽  
Very High ◽  
Delay Variation

Connected Autonomous Vehicles (CAVs) are Not-So-Futuristic. CAVs will be highly dynamic by intelligently exploiting multipath communication over several radio technologies, such as high-speed WiFi and 5G and beyond networks. Yet, the likelihood of data communication loss can be very high and/, or packets arrive at the destination not in correct working order due to erratic and mixed time-varying wireless links. Furthermore, the vehicular data traffic is susceptible to loss and delay variation,which recommends the need to investigate new multipath TCP(MPTCP) protocols for ultra-reliable low latency communication(URLLC) over such heterogeneous networks while reassuring CAVs’ needs. We undertake the challenge by jointly considering network coding and balanced linked adaptation for performing coupled congestion control across multiple wireless paths.Consequently, the proposed low delay MPTCP framework for connecting autonomous vehicles is efficient and intelligent by design. We conduct a rigorous convergence analysis of the MPTCP design framework. In summation, we provide a detailed mathematical study and demonstrate that the latency penalty for the URLLC-MPTCP developed over these networks becomes negligible when considering the possible benefits that multiple network convergence could offer. Our extensive emulation results demonstrate all these lucrative features of URLLC-MPTCP.

Sign in / Sign up

Export Citation Format

Share Document