Marine Navigation Radar

    The Marine Navigation Radar Handbook, or MNR Handbook, Second Edition, is a body of reference about marine navigation radars geared principally for the shipboard ESM operator and shore-based analyst engaged in developing and sustaining maritime domain awareness. This book covers the history, the fundamental physical laws that apply to the domain, the technologies, the governing legislation and the principal manufacturers in the West and Japan. Internet research has yielded technical information on nearly 600 distinct radar designs, from more than twenty manufacturers, while the analysis of many thousands of test-radar measurements yielded highly detailed and reinforced information on over sixty modes of operation for twenty-one known radar systems. The findings from this research and analysis are presented in part here (and in full in the printed Handbook and its accompanying CD). What emerges is a sense of direction, of how modern systems are becoming increasingly complex to satisfy both legal mandates and the self-preserving instincts of the mariner, and hence of how monitoring systems must adapt to changing realities.

         MNR systems have undergone transformation as dramatic in many ways as the weapons systems sensors that attract considerable attention from the world's intelligence communities. Much of this quiet transformation has taken place in full public view but substantially unnoticed, an inevitable consequence of shrinking intellectual capital and the intelligence community's deliberate focus on threat systems and sensors that may jeopardize the integrity of friendly units. Compared with these latter, "exciting" intelligence targets, MNR systems may seem mundane and lacking in report-worthiness; and yet, in a climate where asymmetric warfare is widely espoused and practiced as a counter to overwhelming conventional military might, these humble systems may be used to deliver devastation on a scale previously unimaginable. The potential threat posed by non-military shipping is widely recognized with, for instance, major initiatives in maritime domain awareness (MDA) and broad area maritime surveillance. The purpose of the MNR Handbook is to enhance environmental awareness by illuminating the present "state-of-the-art" in the MNR systems that comprise the vast bulk of today's marine sensor inventory, and by distilling the changes in design and performance specifications that impel the transformation. The intent is that, by drawing together multiple information sources that might ordinarily not come to the attention of the intelligence professional, a clearer picture of the maritime environment will emerge.

         The notion of creating a handbook describing the civil marine navigation radar domain, as a means of capitalizing on engineering resources and data at the Chesapeake Bay Detachment of the US Naval Research Laboratory, coalesced over a span of several years. Among its varied activities, this facility explores monitoring techniques for surveillance of the microwave spectrum and also has a distant site where it conducts long-term testing of marine navigation radars. As far back as 2001, conscious efforts were under way to register the observed behaviors of these test radars, against the day that the data could be turned into information or knowledge. In late summer of 2006, resources became available and work on production of the handbook commenced. From inception to completion of the first edition took a span of six months of research, analysis and documentation, and a further two months of editing.

         Only those engaged in signals analysis can truly grasp the extraordinary differential between traditional processes used to garner and publish knowledge about radar behavior, and those used in the compilation of the MNR Handbook. The most obvious difference is in ready physical access to test systems, with unambiguous correlation of radiated waveforms to specific equipment, which transforms the analytic and reporting paradigm. It is improbable, under any circumstances, that traditional approaches would render as much precise and specific information on radar systems in so short a span as was yielded by the convergence of resources at the Naval Research Laboratory's test facility. It may be difficult to quantify the cost of data acquisition, being a byproduct of tangentially related activities; but the costs of radar-systems acquisition, operation, research and analysis seem certain to be substantially less than those borne by national intelligence authorities with large infrastructures and long-term personnel-, security- and other resource-costs. In sum, the handbook represents a comparatively inexpensive process for presenting timely, unambiguous and incontrovertible knowledge to a community perhaps unaccustomed to such service. 

      The MNR Handbook draws together a diverse range of public-domain information sources and facts derived from a combination of direct inspection, measurement and analysis of signal data from commercial marine navigation radars. Its purpose is to provide a frame of reference for the intelligence producers, sensor systems designers and operational consumers engaged in developing, sustaining and exploiting maritime domain awareness in the interest of national security.

The handbook is divided into four sections:

Historic View

This section comprises a brief review of the development of marine navigation radars, from earliest developments to the emergence of critical components: the magnetron, the duplexer, antenna, echo-plotting devices etc.

The Rule of International Law

This section summarizes legislative processes as they influence the design and performance of marine navigation radars, and discusses the roles of various international bodies in safety of life at sea - IMO, ITU, ICAO, IEC and IALA. Recent International Maritime Organization (IMO) mandates and directives that affect MNR characteristics and capabilities are highlighted, and their significance to the intelligence community, in terms of design and performance, are discussed.


This section describes the basic characteristics of MNRs as mandated by the various international bodies, as a frame of reference. It discusses parameters, physical and logical architectures, etc.

Case Book

This section documents published characteristics for the present product line of most known MNR manufacturers, focusing principally on the "observables" - that is, physical characteristics and measurable radiation characteristics. Information regarding the transmitted waveforms is tabulated, wherever it is available; when documented data is contradictory, these contradictions are noted. Also, in some cases, signal analysis and physical inspection of equipments held on the inventory of the Naval Research Laboratory has been undertaken; these findings are included in the tabulation and discussion. Each case study describes one or more fundamental design from each manufacturer, and a study includes many of the following facets:

* Manufacturer profile and partnerships. 
* A description of fundamental types, potentially including:

Physical design: antenna system; transmitter, receiver and display assemblies.
Parametric limits.
Fundamental timing circuitry.
Pulse-timing sequences and logic.
Upgrade process.

         The first edition of the MNR Handbook contained case studies for Consilium, Furuno, Garmin, GEM Elettronica, JRC, Kelvin Hughes, Koden Electronics, Raymarine, Raytheon, SAM Electronics and Sperry Marine - manufacturers whose products continue to represent a very substantial proportion of today's MNR environment. Some of their products have been retired from product sales brochures, but they are likely to remain in service for a decade or more and have been retained in the second edition.

         Some of the corporate relationships have changed, too, with the most significant being a realignment of previously Koden-associated recreational MNR providers. While they continue to maintain their older product lines that were based on Koden systems, some have been acquired to form an alliance under the umbrella of a newly-formed corporation, Navico. The companies affected by this realignment are Lowrance, Northstar and Simrad; other smaller manufacturers may follow, depending on the success of the new brand. Nonetheless, in this second edition, these smaller manufacturers continue to be grouped as members of "the Koden clan." The most substantial change in this edition, then, is the added clarity of the Raymarine case studies; all of the previous Raytheon Pathfinder series are now shown here, and there is additional material derived from further systems added to the inventory of the Naval Research Laboratory.


    Reader feedback, comments, requests for clarification or amplification, "grist for the mill" in the form of unclassified data contributions, and all related questions of an unclassified nature are invaluable in shaping the usefulness of this Handbook to you, the reader. Please feel free to contact us - the only foolish question is the question unasked, and all communications with the team will be treated as privileged. The Principal Editor has several decades of experience in this particular aspect of maritime domain awareness, other editors in our team bring just as much experience plus a wealth of experience in RF systems design and relevant software-engineering development, and we can track down unclassified information from some of the most obscure corners of the worldwide web. If you want to know about polyrod antennas and their usage in marine radars, or where to find information on new Russian MNRs, or if you simply want to know how we used Excel to 'crack the code' of the stagger pattern used in Raymarine's Pathfinder systems that had the Naval Research Laboratory stymied, please don't hesitate to ask! The full Handbook, with all supporting illustrations, tables and supporting materials, is just too large to be squeezed onto a CD, far too large for a website, and probably too densely-packed with information for most readers. Queries regarding this should be addressed to the Principal Editor.

Principal Editor, EM Forensics
Editor, Wilmark & Associates
Editor, Christman Consulting

Finding your way around the Handbook