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Introduction
Cellular repeaters are the most cost-effective solution to enhancing the coverage of a mobile network, whether in traditional usage such as shadowing areas or specialized application such as in-building or outdoor coverage. Other than the immediate increase in the coverage footprint, other benefits of coverage enhancement are improving network performance and improving utilization of the BTS capacity. With continuous deployment of mobile networks, especially in suburban and rural highways, coverage is most often more important than capacity. In such a situation, an economical mixture of BTSs and repeaters can be employed to offer mobile operators an optimized network with maximum coverage at minimal cost. Because repeaters are simpler than BTS and require much less physical infrastructure, not only capital expenditure costs are minimized, but also operational costs as well. Cellular repeaters can be employed to help mobile operators to spread their coverage and BTS capacity to a wider geographical area, thus enabling operators to reach a more subscribers while at the same time, conserving your upfront investment.
Repeater for The Latest Technology
Remotek repeaters currently support the following mobile systems: GSM, CDMA800, PCS, CDMA2000 and WCDMA system.
Repeater Introduction
1. RF Repeater
A RF repeater is a bi-directional amplifier that allows for the reception of RF signals, amplifies the signal and re-transmits into areas where there is no or very low signal level coverage enabling a mobile user to establish a call connection.
For outdoor areas, BTS' s generally have low utilization of capacity. The surplus capacity can be re-directed to other poor signal coverage area through implementation of a RF repeater. RF repeater can be deployed in towns and rural areas where there are relatively lower numbers of mobile subscribers.
In comparison to a BTS installation, a RF repeater can virtually be installed anywhere that provides a suitable mounting area with a power supply, therefore eliminating the need for an equipment room.
2. Fiber Optic Repeater
A fiber optical repeater is a combination of a RF repeater and optical transceiver modules enabling signal transmission through fiber optical cables to achieve coverage into low signal areas over a fiber distance of 20km
Consisting of a master and remote unit(s), the master unit is usually installed at the BTS site where the RF signal is coupled from the BTS. From the master unit, the RF signal is converted to an optical signal for transmission over the fiber cable to the remote unit. The remote unit receives the optical signal and re-coverts the optical signal back to a RF signal. The signal is then amplified to a higher power level for transmission to the mobile in the low signal coverage area. From the mobile, the signal will be transmitted back to the BTS through the reverse process.
Fiber Optical Repeater is an ideal solution for areas where the geography does not allow for line of sight between the BTS and repeater, the intended coverage area is far from the BTS or for high-rise indoor coverage extension. Typically application areas include villages or sight seeing areas in the mountains, rural or farming areas, underground subways and high-rise building to building groups
3. Frequency Shift Repeater
A Frequency Shifting Repeater is a combination of two RF repeaters with built-in frequency translating module(s) enabling the original frequency to be shifted to a new frequency used as the transmission link between the two repeaters (master and remote repeater units)
The master unit is installed next to the BTS where the signal is coupled from the BTS. Following frequency shifting, the signals are transmitted on a link antenna and received at the remote unit where signals are shifted back to the original frequencies. Finally, the signals are amplified in the remote unit and then transmitted on a service antenna.
By shifting the frequency, the isolation requirements are reduced. In other words, the necessary separation between the pick-up and service antennas at remote site can be low, which means short masts can be used. As the isolation is much easier to achieve through operating on two different frequencies, the gain in the remote unit can be significantly increased so that higher output power is easier obtained and allows the use of antenna(s) to cover 360 degrees at the remote area.
This equipment can be implemented in large areas including lakes, tunnels, highways, small islands, visiting spots, or rural areas.
Applications
The deployment of repeaters for the most part provides operator with the cost-effective solution for coverage extension of indoor or outdoor applications, or to provide coverage to blind areas where communication can not be established.
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