Long-Distance Communications

Long-Distance Communications

 

telephone and telegraph service over wire and radio systems between correspondents located at great (virtually unlimited) distances from each other. The term “long-distance communications” arose in the technology of transmission of electrical signals over wire communications lines; a synonym is “intercity communications,” and an antonym is “local communications” (within a city or raion).

Telephone, telegraph, phototelegraph, and television signals are transmitted simultaneously over long distances over air, cable, and radio communications lines in which hundreds or thousands of independent communications channels are formed by multiplexing communications lines. The use of artificial earth satellites for long-distance communications is promising. To compensate for signal attenuation, attended and unattended (remote-controlled) repeater stations or relay stations with amplifiers for the transmitted signals are installed on some sections of long-distance ground lines. For deep-sea (cable) long-distance communications unattended repeaters with long service life are installed at certain intervals along the length of the cable. Reliable continuous communications are ensured by the use of standby equipment and automated long-distance communications lines.

N. M. IZIUMOV

References in periodicals archive ?
'Development in space research over the past decades has brought about revolutionary advancement in long-distance communications and planetary science.
In a clear case of technological leapfrogging, they have given poor people in developing countries access to long-distance communications without the need for costly investments in landlines and other infrastructure.
It is equipped with six 10/100/1000 Mbps LAN ports (Intel[R] i210 Ethernet controller) and a choice of two or four 10 GbE SFP+ fiber ports for high bandwidth and long-distance communications. The NA362R's I/O options include two USB 2.0 ports and a serial console port.
NEC's simulation trials of the newly developed AAS, which adopts beamforming, a technology for transmitting radio waves in multiple directions (to objects) while intensively and simultaneously using many antenna elements, achieved up to one kilometer in long-distance communications in 16 respective directions on 28GHz high radio frequency bands, at a communications speed of 30Gbps or faster per cell, and spectral efficiency 20 times greater than LTE on a per-communication area basis.
Our Facebook, Twitter, and Linke-dIn presence will be boosted, and we will depend more on webinars and other long-distance communications. Please contact me with your input on how to proceed in these areas.
Previous imaging studies by the NIMH researchers found abnormal tracts of the neuronal fibers that conduct long-distance communications between brain regions, likely resulting from neurons migrating to the wrong destinations during early development.
These technologies include organ transplants, artificial organs, robotics, and nanotechnologies combined with advances in computer and long-distance communications.
"Corporate tenants including business/financial services, healthcare, and education will gain by building in flexibility, using competition in the market to build leverage, and cutting real estate commitments when long-distance communications will meet the need to bring people together."
GE Digital Energy has announced the MDS SD2, a software-controlled digital radio that is said to provide long-distance communications over licensed radio bands and allow users to deploy IP/Ethernet and serial communications using 200 MHz.