WM Systems Universal Industrial RS485 Modem, Руководство пользователя

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LTE
LTE, an abbreviation for Long-Term Evolution, commonly marketed as 4G LTE, is a standard
for wireless communication of high-speed data for mobile phones and data terminals. It is based
on the GSM/EDGE and UMTS/HSPA network technologies, increasing the capacity and speed
using a different radio interface together with core network improvements. The standard is
developed by the 3GPP (3rd Generation Partnership Project) and is specified in its Release 8
document series, with minor enhancements described in Release 9.
LTE is the natural upgrade path for carriers with both GSM/UMTS networks
and CDMA2000 networks. The different LTE frequencies and bands used in different countries
will mean that only multi-band phones will be able to use LTE in all countries where it is supported.
RS232
In telecommunications, RS-232 (Recommended Standard 232) is a standard for serial binary
single-ended data and control signals connecting between a DTE (Data Terminal Equipment) and
a DCE (Data Circuit-terminating Equipment). It is commonly used in computer serial ports. The
standard defines the electrical characteristics and timing of signals, the meaning of signals, and
the physical size and pinout of connectors.
RS485
RS-485 is a standard defining the electrical characteristics of drivers and receivers for use in serial
communications systems. Electrical signaling is balanced, and multipoint systems are supported.
The standard is jointly published by the Telecommunications Industry Association and Electronic
Industries Alliance (TIA/EIA).
This characteristics make RS-485 useful in industrial control systems and similar applications.
RS-485 supports inexpensive local networks and multidrop communications links, using the
same differential signaling over twisted pair as RS-422.
The RS-485 implemented the linear bus topologies using only two wires. The equipment located
along a set of RS-485 wires are interchangeably called nodes, stations or devices.[4] The
recommended arrangement of the wires is as a connected series of point-to-point (multidropped)
nodes, i.e. a line or bus, not a star, ring, or multiply connected network. Star and ring topologies
are not recommended because of signal reflections or excessively low or high termination
impedance. If a star configuration is unavoidable, special RS-485 repeaters are available which
bidirectionally listen for data on each span and then retransmit the data onto all other spans.