Maritime Mobile Research Articles

Satellite repeater arrangement in a new maritime mobile telephone system

A new maritime mobile radio telephone system adopted by Nippon Telegraph and Telephone Public Corporation (NTT), is described. An outline of the technical features of the entire system and the satellite repeater arrangement, adopted to reduce service-dead areas, is given.

Direct-printing telegraph equipment with forward error correction for use in maritime mobile service

Forward error-correction equipment based on cyclic coding, which is applicable for selective calling and direct-printing systems in the maritime mobile service, is described. Some field test results are presented.

H.F. maritime mobile services

The paper surveys the developments in the last 15 years of the h.f. ship-shore communication services provided in the United Kingdom by the Post Office. The first part of the paper deals with the radiotelegraphy services: the international planning at the Atlantic City Radio Conference in 1947; frequency-allocation problems; national planning in the United Kingdom; development of better radio equipments for coast and ship stations; the peace-time development of the joint Admiralty-Post Office Area Scheme for Commonwealth communication with British ships; and the new operational methods for handling the increased volume of traffic. The second part of the paper deals with the developments in the corresponding radiotelephone services with ships and the different frequency-planning and operational problems. The last part of the paper mentions briefly probable future trends, such as the introduction of single-sideband working in the telephony service, selective calling of ships by coast stations to minimize human watchkeeping, data transmission and the use of facsimile for transmission of charts and weather data.

VHF marine mobile systems in British Columbia

The purpose of this paper is to give a general description of the VHF Maritime Mobile facilities of the North-west Telephone Company, who provide this type of service to vessels operating in British Columbia Coastal waters. The present four-channel system, which has been in operation since 1948, will be described. A proposed six-channel system, based on assignments in the 152 to 162 mc/s band in accordance with the 1952 International Agreement, will be outlined.

Technical considerations relating to marine radiotelephone communication for safety

THE International Radio Regulations establishing 2,182 kc as the international calling and distress frequency for maritime mobile radiotelephony in the 1,605-to 2,850-kc band came into effect May 1, 1953.1 Many government stations have been equipped for operation on this frequency. Parts 7 and 8 of the Rules of the Federal Communications Commission (FCC) require that all ships and public coast stations using telephony in this band be equipped for operation on 2,182 kc. Completion of arrangements for the full utilization of this frequency by ship and coast stations in the United States was scheduled for July 1, 1954.