摘要:

the microwave landing system(mls) being developed by FAA under a joint DOT/FAA, DOD and NASA program is designed to meet extended requirements in volumetric coverage, guidance accuracy, and integrity to meet the increasing needs of aviation. It is to be a common civil‐military system and provide a level of operations and equipments suitable for all classes of users.The current Phase III of the FAA Five‐Year Development Program is providing prototype hardware for evaluation and will result in a set of equipment specifications for production equipment. The TRSB has been recommended by an International Civil Aviation Organization (ICAO) technical panel for international standardization. This recommendation will be considered by a meeting of ICAO member states in April 1978.The complete specification of system accuracy is key to the MLS in achieving its operational objectives. There are a number of criteria which this specification must meet. It must provide the guidance accuracy necessary for the intended operations. It must recognize the Flight Control System (FCS) characteristics of the aircraft to be served. It must be expressed in terms which can be measured and also provide design goals for the ground and airborne equipment. The specification must include consideration of the monitor system and the designated alarm limits. This paper presents a proposed accuracy specification for MLS to meet these crite

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01284.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

a formula is presentedfor computing group delay synthetically from phase measurements made at three frequencies. Wave theory indicates that the group delay calculated at the appropriate frequency should be relatively insensitive to the usual diurnal phase variations. This is demonstrated with actual three–frequency phase data for the Trinidad–North Dakota path. The amount of data analyzed is too small to make positive comparisons with composite and other OMEGA configurations, but it is cautiously speculated that the resultant system accuracy using a calculated group delay would be comparable to composite OM

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01285.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

Retransmission of radionavigationsignals enables the location of remote objects in such applications as remote tracking and search and rescue. Previous retransmission systems have used low– and very–low–frequency navaids, all of which have some limitations in coverage, accuracy or ambiguities. The NAVSTAR Global Positioning System, currently under development, will provide highly accurate and unambiguous positioning which will be available continuously anywhere in the world, thereby overcoming the limitations of the low–frequency navaids. The GPS will use L–band carriers which are modulated by pseudorandom noise ranging signals, thereby providing immunity to jamming and multipath interference. These signals are produced by linear feedback shift register generators and are detected by correlation with locally generated codes. Retransmission can be accomplished by translation, remodulation, spread spectrum multiplexing, bandwidth reduction, or preprocessing. The use of preprocessing requires an algorithm for rapid acquisition of the spread spectrum signals; this is accomplished by searching first for setting s

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01286.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01287.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

The development of this fullyMil–qualified stabilized gyrocompass equipment provides a major advancement in military marine navigation. All of the functions of the preceding generation of equipment have been placed into a single–unit, light weight, low–volume console that features the high reliability of solid–state digital electronics and a complete modular insertion maintenance philosophy. Featuring almost twice the precision of the predecessor equipment, this unit meets the needs of a modern Navy, which includes minimum crew/support skill requirements, low life cycle costs and, most important, an adaptable built–in–growth–capability design.The development background of the AN/WSN–2 is discussed in terms of differences and comparisons between conventional marine gyrocompasses versus stabilized marine gyrocompasses and ship's inertial navigators. This is done from a design and operational point of view as well as from a performance/theoretical point of view. In particular the inertial unit of the AN/WSN–2, including the long–life, precision, gas–spin–bearing gyroscope, is the same production equipment currently being used in several thousand airborne inertial navigators manufactured by Litton. Thus a key advantage to the Navy is the fact that this stabilized gyrocompass equipment has gone through a maturation cycle as an inertial navigation system before its selection by the Navy as the new generation stabilized gyrocompass.The AN/WSN–2 is fully described in terms of its system mechanization and physical implementation. Data and analysis of the performance of the AN/WSN–2 demonstrate its ability to meet SHIPS–G–5683, the new stabilized gyrocompass specification generated

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01288.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

the design of an inertiallyaided radio navigation system using a scanning DME interrogator set is discussed, and flight test performance data of this area navigator and of the scanning DME subsystem are presented. Under poor geometric conditions and with 3°/sec turn maneuvers the 1–sigma position uncertainty is about 100 m. In an all–DME standby mode the maximum navigation error was less than 700 m. The navigation system is suitable for area navigation on parallel airlanes. Some operational problems are touched

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01289.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

this paper addressesthe progress being made by the Defense Mapping Agency Hydrographic Center in producing better navigation publications in support of the marine navigator. This progress report includes a brief discussion of the contents of the new edition of Pub. No. 9,American Practical Navigator(Bowditch), which is to be completed late in 1977. This paper also summarizes recent improvements in Sailing Directions, Notice to Mariners, and navigation tables.

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01290.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

The longitude referenceof the Navy Navigation Satellite System (TRANSIT), published in 1971 has been recomputed based on a new geophysical model (WGS 72) and on an improved orbit determination program. The resulting geodetic longitude reference of the updated system agrees closely with the previous one.

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01291.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01292.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

a computer based positioningsystem which combines data from radio navigation aids, the Transit satellite system and a network of underwater, acoustic transponders is described. Particular emphasis is placed on the acoustic subsystem and its integration into the navigation process.The system has been developed by the Magnavox Co., Advanced Products Division and is currently being used for drill rig positioning in the North Sea. A typical operational scenario is described and results from recent applications are discussed.

ISSN:0028-1522    

DOI:10.1002/j.2161-4296.1977.tb01293.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY