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A cellular repeater (also known as cell phone signal booster or cell phone signal amplifier) is a type of bi-directional amplifier used to improve cell phone reception. [citation needed] A cellular repeater system commonly consists of a donor antenna that receives and transmits signal from nearby cell towers, coaxial cables, a signal amplifier, and an indoor rebroadcast antenna.
In the U.S., the analog AMPS standard that used the cellular band (800 MHz) was replaced by a number of digital systems. Initially, systems based upon the AMPS mobile phone model were popular, including IS-95 (often known as " CDMA ", the air interface technology it uses) and IS-136 (often known as D-AMPS, Digital AMPS, or " TDMA ", the air ...
large system; underwent extensive upgrading during the 1990s and is reasonably modern; Telecom Egypt, the landline monopoly, has been increasing service availability and in 2006 fixed-line density stood at 14 per 100 persons; as of 2007 there were three mobile-cellular networks and service is expanding rapidly
A Tower Mounted Amplifier (TMA), or Mast Head Amplifier (MHA), is a low-noise amplifier (LNA) mounted as close as practical to the antenna in mobile masts or base transceiver stations. A TMA reduces the base transceiver station noise figure (NF) and therefore improves its overall sensitivity ; in other words the mobile mast is able to receive ...
Cellular network standards and generation timeline. This is a comparison of standards of wireless networking technologies for devices such as mobile phones. A new generation of cellular standards has appeared approximately every tenth year since 1G systems were introduced in 1979 and the early to mid-1980s.
There are two types of duplex communication systems: full-duplex (FDX) and half-duplex (HDX). In a full-duplex system, both parties can communicate with each other simultaneously. An example of a full-duplex device is plain old telephone service; the parties at both ends of a call can speak and be heard by the other party simultaneously. The ...
The nulls in the radiation pattern of small receiving loops and ferrite core antennas are bi-directional, and are much sharper than the directions of maximum power of either loop or of linear antennas, and even most beam antennas; the null directionality of small loops is comparable to the maximal directionality of large dish antennas (aperture ...
The first cellular network efforts began at Bell Labs and with research conducted at Motorola.In 1960, John F. Mitchell [7] [8] [9] became Motorola's chief engineer for its mobile-communication products, and oversaw the development and marketing of the first pager to use transistors.