撸撸视频

To provide you with an understanding of electromagnetic propagation, antennas and devices relevant to military sensor, communications and electronic warfare systems.

• Course introduction: course structure, aims and objectives,
• Information resources: computer centre, library, information retrieval,
• Propagation: radio propagation, reflection, refraction, multipath, fading, attenuation, ionosphere propagation, troposcatter, anomalous propagation,
• Antennas: fundamental antenna concepts and definitions; impedance match, radiation patterns, directivity, gain, polarization, axial ratio, EIRP, effective aperture, noise temperature, etc.
• Overview of antenna types for communications and radar applications including wire antennas, aperture antennas, reflector antennas, low profile and microstrip antennas,
• Antenna arrays: introduction to phased array theory, types of antenna array, feed network design, beam steering and radiation pattern shaping,
• Electromagnetic devices: high power tubes including magnetron, coaxial magnetron, Klystron, Extended Interaction Klystron and Travelling Wave Tube Amplifier,
• Guided waves: waveguides, coaxial lines, microstrip and other RF planar transmission line structures,
• RF and microwave power dividers, combiners and couplers active solid-state devices: RF diodes and transistors and their application in amplifiers and oscillators, ferrite non-reciprocal devices (circulators and isolators),
• PIN diode switches, modulators and phase shifters.

On successful completion of this module you will be able to:

• Describe the principles of operation and characteristics of antenna sensors and electromagnetic system components and recognise how they may be used in a modern military communication or EW system,
• Identify and explain the various models of propagation of electromagnetic waves in free space and transmission lines,
• Analyse and evaluate the performance of electronic warfare system components,
• Assess the propagation of electromagnetic signals in physical environments,
• Design antenna elements and develop phased arrays performance models.

• Dr Peter Barker

To examine and understand the methods of electronically intercepting, contesting and protecting the information environment generated by communications systems.

• Introduction to Communications Electronic Warfare: Electronic attack, surveillance and defence,
• Electronic Attack: Jamming techniques and effects, calculation of SJNR, jamming of satellite and ground-based links, GPS vulnerability,
• Electronic Defence: ED methods (Burst transmission, antenna null-steering, error control, spread-spectrum techniques),
• Comms EW receivers: Requirements, sensitivity and dynamic range of intercept receivers; communications ESM receiver types (swept superhet, channelised, FFT-based channelised),
• Direction-finding: DF techniques (DF loop, Adcock antenna, rotary DF systems, interferometers, time difference of arrival method, pseudo-Doppler techniques, amplitude comparison methods); Commercial DF and military EW systems:; Geolocation,
• Military tactical data links: a case study of high-level EW protection applied to a military data network,
• Spectral estimation: Classical and parametric methods, eigenvector-based methods,
• Guest lectures from defence industry.

On successful completion of this module you will be able to:

• Identify the main electronic surveillance (ES) and electronic attack threats (EA) to a communications system and propose defensive measures to reduce the impact of these threat,
• Explain the main analysis methods employed in communications EW in the time, spectral and spatial domains,
• Analyse and evaluate the impact of electronic attack on a communications network using a power budget and quantify the effect of electronic defence measures.

To provide you with an understanding of the subjects supporting the specialist modules and to provide you with the essential signal analysis and statistical tools used in the course.

• Statistics and Noise: Probability, random variables, probability distributions, covariance, correlation. Noise sources, noise bandwidth, noise figure, noise temperature. Cascaded networks. Mathematical representation of noise,
• Analogue and Digital Signal Processing 1: Analogue methods used to describe, analyse and process signals and the behaviour of systems: Fourier and Laplace transforms, correlation and convolution, impulse response and transfer function,
• Analogue and Digital Signal Processing 2: Matched filters, the z-transform. Advantages/ disadvantages of DSP, sampling and quantisation, digital filters, DFT and FFT, DSP applications in communications and radar,
• Decision Theory: Hypothesis testing, probabilities of false alarm and detection, Bayesian systems, error probability and bit error rate, receiver operating characteristics. Bit-error rate lab demo.

• Describe the signal processing methods commonly encountered in sensor, communications and EW systems,
• Evaluate the effect of randomly varying signals on the decision processing in sensor and communication systems,
• Identify and analyse signal and noise waveforms commonly encountered in communications, sensor and electronic warfare systems in the time and frequency domains,
• Analyse the detection performance of such systems.

To provide you with an understanding of the concepts and techniques employed in modern communication systems.

• Introduction: Transmitter and receiver communications system model,
• Voice source coding: Pulse code modulation, delta modulation, vocoders, demonstrations,
• Analogue modulation: Amplitude modulation, DSB/SSB. Frequency modulation, demonstrations,
• Digital modulation: ASK, FSK, PSK, DPSK, QPSK, Offset QPSK, MSK, QAM, demonstrations,
• Communications channel: Multipath effects, fading and diversity, Egli and Murphy,
• Receivers: superheterodyne systems, balanced and unbalanced mixers, frequency synthesisers,
• Link budget analysis.

On successful completion of this module you will  be able to:

• Identify the main functions of each of the component blocks in a communications system model, deriving suitable values for each of the system parameters,
• Describe the principles, implementation and theoretical background of the principal modulation schemes employed in communication systems,
• Evaluate the effects of a communications channel on a transmitted signal in terms of attenuation, time, frequency and phase dispersion,
• Analyse the performance of a communication system based on a link budget, using a standard propagation model,
• Propose a suitable communications architecture to meet a required specification given a particular application.

To provide the you with an understanding of how modern military and commercial communications systems utilise the principal techniques taught during the communications principles module.

• Multiplexing and multiple access: FDM, TDM, statistical multiplexing, multiple access methods FDMA, TDMA and CDMA,
• Fibre-optic communications,
• Error correction codes: Block, convolutional and trellis coding. LDPC and Turbo codes,
• Wideband multicarrier techniques: Spread spectrum techniques, OFDM. MIMO systems,
• Cryptography: Terminology, secret key and public-key systems, authentication, key exchange,
• GSM: 1G and 2G cellular radio systems. GSM system architecture, signalling, framing and frequency bands,
• GPRS and EDGE: Enhancements to GSM. 3G systems and signalling,
• 4G systems and signalling, 5G developments,
• HF systems. Scatter-based systems,
• Software Defined Radio,
• Satellite communications,
• GPS. System description,
• Military Communications Systems.

On successful completion of this module you will be able to:

• Assess and evaluate the modern communications systems studied in terms of their performance in a hostile environment,
• Model and analyse the performance of key components within modern communication systems,
• Relate the performance of a modern military communication system to its design characteristics.

To provide you with an understanding of networks in a modern military electronic sensor or communications system, their vulnerabilities and how they can be protected.

• Communicating data and the function of networks,
• Military network requirements,
• Building a local area network (LAN): media, devices and protocols,
• Internet history, addressing and services, including the role of Internet authorities and registries,
• Internet architecture and protocols,
• IP addresses and domains,
• Reliable communication,
• Layered models: The Open Systems Interconnection (OSI) and Internet models,
• Wide area networks (WANs) and routing,
• Network security,
• Network analysis and monitoring,
• Wireless networks,
• Mobile ad hoc networks (MANETs),
• The World Wide Web(WWW),
• Network modelling, simulation and emulation.

On successful completion of this module you will be able to:

• Recognise how a network may be exploited in a military context to support information age operations and to identify the benefits of such support,
• Identify the various components of a network and its architecture, defining the protocols and address structure, such that network infrastructure solutions can be critically assessed,
• Describe and explain the operation of a wireless LAN,
• Propose a secure wireless network structure, evaluating the level of security that such a network can provide against likely threats,
• Critically analyse trends and technological developments in networking, identify the threats to a network and then evaluate the responses and defence measures to counter these threats.