Radar Coastal Surveillance - Essay Example

Table of Contents Table of Figures 2 0 Research Approach 3 1 Aim 3 2 Research Question 3 3 Methodology 3 Introduction 4 2 Background 4 2.2 Definitions 5 2.3 Historical Overview 6 3.0 Radar Purposes and Technology 7 3.1 Radar Engineering 8 3.1.1 Reflection 8 3.1.2 Radar Equation 9 3.1.3 Polarization 10 3.1.4 Interference 11 Radar Systems 12 3.2.1 Radial Velocity Discrimination 12 3.2.1.1 Differentiation 13 3.2.1.2 Moving Target Indicator (MTI) 13 3.2.1.3 Pulse Doppler Radar 16 3.2.1.4 Limitations 18 3.2.2 High Resolution Radar 18 3.2.2.1 Pulse Compression 18 3.2.2.2 Synthetic Aperture Radar 19 3..2.2.3 Inverse Synthetic Aperture Radar (ISAR) 22 Coastal Surveillance Requirements 24 4.1 Purpose of Coastal Surveillance 24 4.1.1 Surface Search Radar Systems 25 4.1.2 Disadvantages 26 4.2 Raytheon Canada Ltd.: An Ideal System 27 5.0 Discussion and Recommendation 29 5.1 Existent and Future Needs 29 5.2 Costal Surveillance System Recommendations 30 5.2.1 Authentication, Authorization and Accounting 31 5.2.2 Intrusion Detection and Prevention 34 5.2.3 System Overview 35 Concluding Remarks 35 6.0 References 36 Table of Figures Figure 1. Phase comparison output. 14 Figure 2. Five sequential returns from pulse comparison output. 15 Figure 3. Cancellation circuit of MTI processor. 16 Figure 4. Pulsed Doppler radar system. 17 Figure 5. Pulsed Doppler display. 17 Figure 6. Pulse compression using frequency modulation. 19 Figure 7. Overlapping returns separated by frequency. 19 Figure 8. Synthetic aperture. 20 Figure 9. Equivalence of SAR and ISAR. 22 Figure 10. Coastal Surveillance Functions. 30 Figure 11. Surveillance Structure. 33 Figure 12. Port Monitoring System. 34 1.0 Research Approach 1.1 Aim The primary aim of the present research is the determination of the extent to which radar systems efficiently and effectively execute the requirements and tasks associated with coastal surveillance. Hew (2006), a defence systems analyst with the Defence Science and Technology Organisation, contends that no single radar system is capable of fulfilling the stated tasks and responsibilities but that coastal area characteristics have to be matched against specific systems. In other words, the selection of the coastal radar selection system is dependant upon the characteristics of the coastal area in question and no radar system addresses the needs and features of all. Proceeding from an acknowledgement of this argument, this study will review all of radar technology, coastal surveillance requirements and existent methods for radar coastal surveillance to determine the optimal system, or systems for the execution of coastal surveillance responsibilities. 1.2 Research Question Within the limits of present radar technologies, which radar system(s) can best fulfil the needs and requirements of coastal surveillance 1.3 Methodology As a strategy for responding to the selected researched question and satisfying the research's articulated aim, an in-depth investigative exploration of radar technology, coastal radar systems, and the requirements of coastal radar surveillance shall be undertaken. The results of the investigation shall determine the optimal coastal radar surveillance system(s). Introduction Prior to presenting the data upon which the discussion pertaining to the research question shall be based, it is necessary to contextualize the report's focus. This shall be done through a review of the definition for radar systems, an historical analysis of its development and the articulation of its responsibilities and tasks. 2.1 Background Practically all systems, from computer and communication systems to air and naval defense systems may ultimately be identified as multi-tasking technological networks, comprised of several asynchronous parallel distributed operations and whose total response is, by definition, both complex and probabilistic. Further evidencing the inherently complex nature of systems is the fact that operational responses vary in accordance to output events (Harmon, Landreth and Lausch, 198). As directly pertains to radar systems, the validity of the aforementioned is upheld by the complex nature of radar system operations and responsibilities, as shall be established in the below definitional and operational overviews. 2.2 Definitions Making its first appearance in scientific and academic literature in 1941, the term RADAR is an acronym for Radio Detection and Ranging. That is not to imply that the technology did not evolve until 1941 since, as Perry and Keridis (2004) explain, prior to the development of the stated acronym, the technology in question was popularly referred to as Radio Detection Finding, abbreviated as RDF. Over the past decades, the capitalization associated with the acronym was abandoned and the term, radar, was absorbed into the English language (Perry and Keridis, 2004). Academic and scientific definitions for the term radar are straightforward and uncontested. As defined, radar systems are ones which use electromagnetic waves for the purpose of identifying all of the location, direction and speed of both fixed and moving objects, further serving to identify weather formations and terrain. Radar systems have multiple purposes or, to rephrase, are used in several contexts, including military aviation and naval purposes, meteorological detection of precipitation levels and traffic and speed control (Streetly, 2005). The military coastguard typically uses radar systems for the surveillance of coastal regions. To understand precisely what such a task involves, it is necessary to define the study's second key term, surveillance: "The systematic observation of aerospace, surface, or subsurface areas, places, persons, or things, by visual, aural, electronic, photographic, or other means" (Hew, 2006: n.p.). On the basis of the definitions offered in the above, coastal radar surveillance may be defined as the strategy by which the coastguard, or military in some instances, monitors activity on and around the coastal regions for the purpose of detecting and identifying any abnormal occurrence or objects, often for security, defense or rescue goals. 2.3 Historical Overview A tracing of the historical roots of radar systems leads one back to Germany, at the dawn of the twentieth century. In 1904, the German scientist, Christian Hulsmeyer established the veracity of his hypothesis regarding the possibility of detecting distant metallic objects through radio waves by producing the first working model. The Hulsmeyer model was able to detect the presence of a distant off-shore ship but was not able to calculate its distance. The Hulsmeyer model, referred to in scientific and technological literature as the pre-radar, was the staring point for the development of the radar as defined and discussed in the above (Miekle, 2001). From 1904 to World War II the British, the German, the French and the Americans made significant strides in radar research and development. It was World War. It was, however, the war which provided the real impetus for radar research and development as its potential for surveillance and defense were identified as highly significant. Hence, the war period witnessed intensified research and development in radar, aiming towards the attainment of better resolution, more probability and, of course, more features. The efforts paid off and the radar lived up to its expectations and potentials. Today, it is used, in a wide array of fields, both military and civilian. It is employed in air trafficking control, weather monitoring, coastal surveillance, airspace surveillance, space surveillance and road speed control purposes (Miekle, 2001; Skolnik, 2002). 2.4 Report Structure The report shall be comprised of five sections. The first shall introduce the research's aims, question and selected investigative methodology and the second shall overview the background, definition and history of both radar technology and radar surveillance. The third section of the report shall present the purposes of radar technology, radar engineering principles and the different radar surveillance systems. The fourth section of the report shall outline the requirements of coastal surveillance and the more popular radar systems used for the satisfaction of those purposes. The fifth and final section shall discuss the study's findings and present a set of recommendations, in response to both the research aims and question. 3.0 Radar Purposes and Technology Radar systems carry out the function of surveillance through a process of intercommunication between its various components., those being the transmitter, the receiver and the display Quite briefly stated, a transmitter emits the radio waves which are reflected by a target and subsequently detected by a receiver. The wavelengths used are customarily on the order of 10 cm and correspond to frequencies of approximately 3GHz. Detection and ranging tasks are executed through the timing of the gap between the transmissions of a pulse of radio energy to its return. As radio signals can be very low, they are often amplified (Perry and Keridis, 2004). The complexity of the radar system is largely obscured by the foregoing explanation of its operation. A more detailed, hence more accurate, explanation of its engineering framework and principles shall, therefore, be presented. 3.1 Radar Engineering The technical and engineering principles upon which the radar system rests are both complicated and complex. Nevertheless, if the report is to present a comprehensive response to its selected research question, radar principles need be stated and briefly defined. 3.1.1 Reflection The first of radar engineering's principles is that of reflection. This principle maintains that any significant change in dielectric/diamagnetic constant will be reflected in electromagnetic waves. In other words, changes in the atomic density of an object and its immediately surroundings will scatter radar/radio waves, allowing for the detection of abnormal occurrences and activities. The stated principle is particularly true, or operates ideally, insofar as electrically conducive metals and materials are concerned among which, of course, are ships and most all forms of sea vessels (Briggs, 2004; Tait, 2006). Reflection is particularly useful both in ascertaining the size of an object and in the detection of small objects. The scatter pattern of radio waves is largely determined by the length of the waves themselves. If the wavelengths are significantly shorter than the target's size, waves bounce of in a manner comparable t the reflection of light on a mirror. Conversely, is the wave lengths are significantly longer, the target is polarized, creating a Rayleigh scattering effect. When wavelengths and target size are equal, resonance may occur. Modern radar systems use short wave lengths of just a few centimeter because they are especially suited for surveillance purposes, capable of imaging very small objects (Briggs, 2004; Tait, 2006). 3.1.2 Radar Equation The following radar equations are representative of the second radar principle. In the below, the power Pr returning to the antenna is as below: where Pt = transmitter power Gt = gain of the transmitting antenna Ar = effective aperture (area) of the receiving antenna = radar cross section, or scattering coefficient, of the target F = pattern propagation factor Rt = distance from the transmitter to the target Rr = distance from the target to the receiver. In instances where the transmitter and receiver are in the same locale, In, Rt = Rr and Rt2 Rr2 can be replaced by R4, where R is the range: As indicated, received power declines at the fourth power of the range, indicating that reflected power from distant targets is minuscule. 3.1.3 Polarization Within the parameters of the transmitted radar signal, the third radar principle is based on the fact that, in such instances, the electrical field is perpendicular to the propagation direction, and the electric field direction is the polarization of the wave. For further explication of the import of the stated, it is necessary to recall that radars use all of horizontal, vertical, linear and circular polarization to detect different types of reflections. Polarization is critically important, whereby circular polarization minimizes interferences caused by rain; random polarization indicates a fractal surface; and linear polarization is indicative of a metal surface (Briggs, 2004; Tait, 2006). 3.1.4 Interference Radar systems must overcome several different sources of unwanted signals in order to focus only on the actual targets of interest. These unwanted signals may originate from internal and external sources, both passive and active. The ability of the radar system to overcome these unwanted signals defines its signal-to-noise ratio (SNR): the higher a system's SNR, the better it is in isolating actual targets from the surrounding noise signals (Briggs, 2004; Tait, 2006). Radar Systems 3.2.1 Radial Velocity Discrimination Radial velocity discrimination is integral to radar system operations and functions, such as coastal surveillance because of the imperatives of being able to assess a target's range and radial velocity. To the extent that relative radial velocity represents the range rate, measurements of radial velocity are conducted to access the target's near future range . For coastal surveillance purpose, this is highly important because it allows for the elimination of unnecessary sea clutter from the display (Streetly, 2006). 3.2.1.1 Differentiation Insofar as coastal surveillance is concerned, the differentiation measurement system is highly important. Based on the measurement of range at fixed intervals, followed b the computation of variances, the target's range rate, and differences therein, may be accurately measured. 3.2.1.2 Moving Target Indicator (MTI) As with differentiation, MTI is essential for the purposes of coastal radar surveillance because it functions to measure and determine target motions. It does so by measuring changes in the phase of returned signals, in which case, a sample of the transmitter pulse in entered into a phased computer, as is a sample of the returned signal. The phase comparator output then modulates the display information. When in-phase, returns are at their largest and positive and when out phase, returns are at their largest negative value.' Figure 1. Phase comparison output. As the range to a target undergoes change, this will be reflected in phase comparison outputs which will subsequently vary between extremes and move in range. Figure 2. Five sequential returns from pulse comparison output. Stationary targets, as defined by the coastguard/navy/military, for surveillance purposes, are targets whose returns do not exhibit change in range, while moving targets are ones whose returns do indicate change in range. Since stationary targets have a fixed phase value, it is possible to exploit differences so as to eliminate them from the display. The methodology for doing so is straightforward. As moving targets average zero, stationary targets will have a non-zero average, allowing for the subtraction of the average signal from he output prior to display, thus eliminating stationary targets from he display (Skolnik, 1990; Skolnik, 2002; Le Chevalier, 2002). Figure 3. Cancellation circuit of MTI processor. 3.2.1.3 Pulse Doppler Radar The advantage or strength of the PDR is that it contains additional processing technologies. A sample of the transmitted signal is sent for processing to the mixer which also samples receiver output. The resultant output is the Doppler shift, passed to a filter for the modification of output display. The colour coded nature of the display allows facilitates absorption of information, at a glance (Streetly, 2006). Figure 4. Pulsed Doppler radar system. Pulsed Doppler radar systems are particularly useful for coastal surveillance purposes as well as for military surveillance tasks in general. Figure 5. Pulsed Doppler display. 3.2.1.4 Limitations Despite their articulated advantages and even though the basic radar systems discussed are used for coastal surveillance purposes and often with good results, the fact is that they are constrained in their capacities to fully execute the requirements of coastal surveillance because of an inherent technological limitation. In brief, neither Doppler nor MTI radar system can measure velocities at the first blind speed, or above a particular predetermined value. Indeed, targets moving at the first blind speed or above a certain value will appear stationary (as they cannot be measured) and, as such, will be cancelled from the display (Skolnik, 1990; Skolnik, 2002; Le Chevalier, 2002). 3.2.2 High Resolution Radar 3.2.2.1 Pulse Compression This is a method which combines the high energy of a long pulse width with the high resolution of a short pulse width. The pulse is frequency modulated, which provides a method to further resolve targets which may have overlapping returns. Since each part of the pulse has unique frequency, the two returns can be completely separated (Skolnik, 1990; Skolnik, 2002; Le Chevalier, 2002; Streetly, 2006). Figure 6. Pulse compression using frequency modulation. The receiver is able to separate two or more targets with overlapping returns on the basis of the frequency (Skolnik, 1990; Skolnik, 2002; Barton, 2004; Le Chevalier, 2002). Figure 7. Overlapping returns separated by frequency. 3.2.2.2 Synthetic Aperture Radar Synthetic aperture radar (SAR) uses the motion of the transmitter/receiver to generate a large effective aperture. In order to accomplish this, the system must store several returns taken while the antenna is moving and then reconstruct them as if they came simultaneously. If the transmitter/receiver moves a total distance S during the period of data collection, during which several return pulses are stored, then the effective aperture upon reconstruction is also S (Le Chevalier, 2002). Figure 8. Synthetic aperture. The most frequent application of SAR is with satellite radar systems. Because the satellite is travelling at high velocity, the accuracy of these systems can be made very high. Furthermore, if the target is fixed in location, the period for data collection can be made very long without introducing significant error. Therefore satellite SAR is used for the imaging of fixed objects like terrain, cities, military bases, and such (Le Chevalier, 2002). 3..2.2.3 Inverse Synthetic Aperture Radar (ISAR) It is possible to achieve the same large synthetic aperture without moving the transmitter/receiver. If the target rotates by a small amount, it has the same effect as if the transmitter/receiver were to travel a distance equal to the arc length at the range R. The figure below illustrates this effect for a yaw angle of a ship at range R (Skolnik, 1990; Skolnik, 2002; Le Chevalier, 2002). Figure 9. Equivalence of SAR and ISAR. ISAR systems are typically used for long-range imaging and identification of possible targets. The ISAR platform may be fixed or moving. The best targets for ISAR are ships which tend to yaw periodically in the sea state (Skolnik, 1990; Skolnik, 2002; Le Chevalier, 2002). Coastal Surveillance Requirements As may have been deduced from the foregoing presentation of radar engineering and the various types of radars exploited for surveillance purposes, as advanced and as complex as the technology in question may be, there are inherent limitations to each of the systems reviewed. Nevertheless, at this stage it is, as yet, too early to determine which system is optimally suited for the purposes of coastal surveillance. Indeed, determination of the aforementioned is, first and foremost, predicated on an understanding of the purposes and requirements of coastal surveillance. Hence, this section of the study shall present the requirements, responsibilities and needs of coastal surveillance, following which the more popular methodologies for its execution shall be presented. 4.1 Purpose of Coastal Surveillance The purpose of coastal surveillance is simultaneously complex and simple. Its simplicity arises from the fact that the aim of such surveillance is, in straightforward terms, the protection of coastal regions from penetration by unauthorized objects, including both vessels and aircrafts. That is its primary objective, although radar systems serve the added, essential purposes, of weather monitoring, determination of marine pollution risks and such. For the purposes of this report, however, the primary objective of coastal surveillance is the detection of potential threat and the identification of objects entering territorial waters. The seeming simplicity of the objectives of coastal surveillance obscures the complexity associate with the performance of such a task. As Kendall (2003) explains, coastal surveillance is a highly complex task since its efficient and effective operation is immediately dependant on the capacity of the systems used to detect objects of varying sizes, to distinguish varying types of vessels from sea clutter and to be able to communicate with the detected vessels for the purpose of determining whether or not they can be classified as a threat. Detection and Search radars have been identified as the most suited for the purposes of coastal radar surveillance and, more specifically, the Surface Search category of radar systems therein. In order to establish the presence of a fit' between the named radar system and the goals of coastal surveillance it is necessary to correlate between the capabilities of the former and the requirements of the latter. 4.1.1 Surface Search Radar Systems Surface Search Radar systems have been identified as optimal for the purpose of coastal surveillance for one simple reason. SSR's are capably of executing 360o sweeps over a coastal area in periodic, continuous cycles for the explicit purpose of searching for new entrants into the surveillance area. The identification of objects/vessels as new entrants is enabled through data comparison, whereby previously detected objects are compared against the current state for the determination of any developments (Barton, 2004). The surface search capacities, concomitant with the ability to detect new entrants into the surveillance area, establish SSR systems as ideally suited for the purpose of coastal surveillance. As earlier stated, the penultimate objective of coastal surveillance is the protection of areas from the entry of illegal vessels and/or objects, thereby allowing for the proactive defence and protection of the areas in question. Insofar as they undertake the requisite search and detection tasks, SSR systems have been identified as optimally suited for coastal surveillance purposes. 4.1.2 Disadvantages The primary disadvantage of SSR systems lies in their current technological limitations. As Kendall (2003) notes, while many of the systems therein are capable of detecting small objects at a distance, they are fundamentally incapable of distinguishing between sea clutter and vessels. Accordingly, as such systems identify potential threat according to AIS reception and subsequently enabling vessel identification, erroneous threat reporting tends to be high, including as it does all that which does not emit the requisite transmission, sea-clutter and otherwise. Richards (2005) concurs with the above explicated disadvantage but adds another, possibly more significant one. As he notes, the imperatives of high speed surface scanning, especially if the surveillance area in question covers an entire coastal region, are incontrovertible. Quite simply stated, lapses in scan cycles imply the risk of unauthorised vessels entering undetected. While Richards (2005) concedes that the prevalence rate fir such incidents is low he, nevertheless, emphasises its occurrence and stresses that it undermines the very purpose of coastal surveillance systems. It is, thus, that he emphasises the imperatives of developing a high-speed surface scanning system which can, additionally, distinguish between vessels and sea clutter. 4.2 Raytheon Canada Ltd.: An Ideal System There are countless commercial SSR systems designed for the purposes of coastal surveillance. Among the most favoured coastal surveillance radar equipment producers/manufacturers are: Easat, NAVTEX SSR Engineering Radwar PIT Raytheon Northrop Grumman BAE Systems EADS Each and every one of the available systems, however, has both its advantages and disadvantages. Speaking from within the context of a post-September 11th world, however, there is little room for the toleration of system weaknesses and disadvantages. It is, thus, that Williams argues both the imperatives of investing in the research and development of a foolproof coastal surveillance system which, importantly, is user-friendly while, at the same time exploiting available technologies to devise what is as close to that (ideal) system as possible. Following a review of the coastal, harbour and port security systems installed in some of the world's busiest and most important ports, the researcher has decided that the coastal surveillance system provided for military and commercial use, specifically port, coastal and harbour security, by Raytheon Canada Ltd., constitutes that which most closely resembles the ideal. This is because it overcomes the inherent limitations of each technology by supplementing it with another, with the result being a coastal surveillance system which combines between four existent technologies: Long-Range HF Surface-Wave Radar (HFSWR); Automatic Dependent Surveillance (ADS) Systems; Other sensor systems; Multiple-Sensor Data Fusion and displays. The above named surveillance technologies compliment and supplement one another but whether or not it can be categorised as the ideal system (within, of course, the limits of present technology) for coastal surveillance, shall be explored in greater depth in the succeeding section. 5.0 Discussion and Recommendation Prior to the provision of any recommendations, it is necessary to take a closer look at existent coastal surveillance needs and requirements, taking into account potential needs and hence, extending beyond the needs' discussion presented in the preceding section. 5.1 Existent and Future Needs Coastal surveillance is geared towards the monitoring of port, harbour and coastal areas for security purposes while ensuring that the said monitoring/surveillance does not disrupt vessel traffic. The securitization of coastal areas includes all of the prevention of illegal smuggling activities, the stoppage of unauthorized vessel entries and the safeguarding of the areas in question against illegal immigration. It is expected that the stated needs shall become both more intense and urgent in the future as traffic increases, smuggling activities continue to proliferate and multiple factors incite greater levels of illegal immigration. 5.2 Costal Surveillance System Recommendations Figure 10. Coastal Surveillance Functions. The functions of coastal surveillance are detection, investigation, prevention and authentication, authorization and accounting. In other words, the system detects entrants in the surveillance area, investigates the identity of the entrants, authenticates identity and subsequently authorizes entry and, in instances where the entrant is identified as a potential threat, its prevention. Accordingly, such systems play a seminal role in the protection and securitization of coastal regions. As may be deduced from the above-mentioned, however, and as earlier noted, the said functions are extremely complex and given high traffic volumes, both lawful and non-lawful, quite difficult. Difficulties are exacerbated by the limitations of the equipment used, the details of which were outlined in the preceding section. Following a review of existent and future coastal surveillance requirements, the researcher determined that, consistent with manufacturer claims, the ideal system is Raytheon Ltd.'s, currently installed and operational in the Netherlands and Portsmouth, USA. The identified system has numerous advantages, not least of which is that it combines between four technologies, those being HFSWR, ADS, Multiple-Sensor Data Fusion and displays and several other sensor systems. Added to that, it has quite nearly automated the coastal surveillance process through a myriad of software and technological systems. This can best be explained by outlining the way in which the system executes each of the identified coastal surveillance functions. 5.2.1 Authentication, Authorization and Accounting This set of function is carried out through a smart gate, or communication system at the entry of the port in question, comprised of several components, each of which work together for the provision of a holistic and comprehensive AAA system. The smart gate system is comprised of all of the below: Smart buoys: They are equipped with RF interfaces and the appropriate supporting computer technology. They monitor and survey their immediate surroundings and communicate the data gathered to the main security centre through a wire link. iBoat (intelligent boat): These are remote controlled boats which are installed with the same technology and equipment as are the smart buoys but, rather than survey immediate surroundings, they can be navigated around the surveyed area, collect additional data, including the vessel identifier data, which they then relay to the security centre via the smart buoys. AIS (automated information system): This is integral to the identification of ships and the confirmation of their identity prior to their passage through the secured area (area beyond the smart gate). Cargo monitoring software: Not withstanding the importance of identifying and authenticating the identity of vessels, the monitoring of vessel cargo is equally important. Cargo monitoring software should, needless to say, be capable of handling large volumes of data, as in incoming information regarding cargo, and process that data for possible detection of such inconsistencies as would signify a possible attempt to obscure the true nature of the cargo in question. The Raytheon system, as in the one which is being recommended by this report as the optimal coastal surveillance system, has precisely such software. More importantly, the cargo monitoring software sounds of an alert to the defined security centre upon the detection of any possible inconsistencies, thereby allowing port security officers to take the necessary precautions. Near-time data warehousing: This is a software databases system whose primary intent is to gather data on cargo and vessels for future reference. It actually services as a threat detection system and a point of authentication. It compliments and works alongside the cargo monitoring software. Figure 11. Surveillance Structure. Figure 12. Port Monitoring System. 5.2.2 Intrusion Detection and Prevention This part of the coastal surveillance system compliments the functions of that outlined in the preceding. The primary differences lies that its penultimate aim is the prevention of any form of physical intrusion. To do so, it the system monitors the Surveilled area through all of sight, sound and thermoception, exploiting the following technologies for the said purpose: Radar systems Sonar systems (for either underwater or on-water threats) Closed circuit television (CCTV) Perimeters High-tech door locks (biometric systems) Supporting communication and software that can handle alarms 5.2.3 System Overview As evidenced in the foregoing overview of the Raytheon Coastal Surveillance System, it is, as claimed by its manufacturers, the most advanced and comprehensive system available. Its advantages lie in that it exploits an array of existent technologies in order to compensate for the limitations of each, thereby creating a comprehensive surveillance system, designed to address the existent and future needs and requirements of coastal surveillance. Concluding Remarks In concluding this report, it needs to be stressed that the presented recommendation is general at best. The reality is that the specifics of each coast vastly differ and alongside the stated difference are variances in the system which would best address the area's specified needs. Accordingly, rather than interpret the researcher's recommendation as support for the adoption and implementation of the identified system, it should be interpreted as support for the system as a generic model for coastal surveillance. 6.0 References Barton, D. (2004). Radar System Analysis And Modeling. Norwood: Artech House. Briggs, J.N. (2004) Target Detection by Marine Radar (Iee Radar, Sonar Navigation and Avionics). Herts: IEE. Harmon, J. Landreth, J. and Lausch, D. (1983). A development of methodology applied to radar system simulation.' Proceedings of the 1983 Winter Simulation Conference, 409-418. Hew, P.C. (2006) Visualisation of surveillance coverage by latency mapping.' ACM International Conference Proceeding Series, 142, n.p. Kendall, B. (2003) An overview of the development and introduction of ground radar to 1945.' The Journal of Navigation, 56, 343-352. Le Chevalier, F. (2002) Principles of Radar and Sonar Signal Processing. Norwood: Artech House. Leung, H. (1995). Applying chaos to radar detection in an ocean environment: an experimental study.' IEEE Journal of Ocean Engineering, 20 (1), 56-64. Miekle, H.D. (2001) Modern Radar Systems. Norwood: Artech House. Perry, C. and Keridis, D. (2004). Defence Reform, Modernisation and Military Cooperation in Southeast Europe. Herndon: Bassey's. Skolnik, M.I. (2002) Introduction to Radar Systems. London: McGraw-Hill. Skolnik, M.I. (1990) Radar Handbook. London: McGraw-Hill. Streetly, M. (2006) Jane's Radar & Electronic Warfare Systems 2005-06. NY: Jane's Information Group. Tait, P. (2006) Introduction to Radar Target Recognition. Herts: IEE. Williams, P.D.L. (1998) Civil marine radar: A review and a way ahead.' Journal of Navigation, 51, 394-503. Read More