The purpose of a cell phone repeater is to amplify cellular signals for transmission. This device is mainly used in areas where cellular network reception is poor due to reasons like distance from the nearest cellular tower, environmental factors, construction materials used in buildings, and so on. Signal boosters are also available for vehicles to improve network connectivity and thereby call quality while traveling, especially through areas with bad cellular reception. This article will best attempt to answer various aspects of cell phone signal strength enhancement using a cell phone repeater.
An Overview Of Cell Phone Repeater
Most commercial and residential cell phone repeaters are multi-band devices, i.e. they can utilize multiple frequency bands used by cellular carriers, and this improves their performance. They consist of three main components, i.e. the outside antenna that receives the weak cellular signal, a bi-directional amplifier that boosts cellular signals for transmission, and the inside antenna for broadcasting boosted cellular signals. These devices are usually provided by cellular carriers or are available from vendors authorized by the carrier. Besides, a signal booster boosts the signal from either a single carrier or multiple carriers. Furthermore, when purchasing these devices, you must ensure that they are certified by the national telecom regulatory agency.
The main factor that determines the performance of a cell phone service booster is the gain of the amplifier. It is the number of times the strength of a weak cellular signal is boosted; the higher the better. In a signal booster, the gain is adjusted to get the optimal performance. This is mainly determined by the distance between the internal and external antennas, as well as the strength of the cellular signal received by the outside antenna. Also, keep in mind that for indoor purposes the gain should not be more than 70dB, and the noise, less than 6dB.
Operating Frequencies Of A Cell Phone Service Booster
Multiband signal boosters offer better performance, and hence dual- and tri-band systems cost significantly more. Apart from this, signal boosters are available for satellite phones as well. They must be compatible with currently used cellular communication technologies like 4G and 3G. Above all, you must ensure that the booster system is designed to operate in the frequency range used by your cellular carrier. Also, keep in mind that signal boosters are going to play a significant role in the deployment of 5G networks.
The Cell Phone Service Booster
There are three main components in a cell phone signal booster, and they are the external antenna, the bi-directional amplifier, and the internal antenna.
The External Antenna:
The external antenna receives cellular signals to be amplified by the cell phone repeater. So, the performance of this device depends on the type of antenna used. In remote places like rural areas with bad cellular network connectivity, directional antennas are used. It has a high forward gain and hence gives usable signal strength. Besides, as the name suggests, they receive signals from the direction in which they are pointed, and this is usually towards the nearest cellular tower.
A bi-directional amplifier consists of different modules that work together to get the best output, i.e. boosted signal. The different modules are duplex filters, LNA (low noise amplifier), bandpass filter, and power amplifier. A boosted signal from the amplifier is sent to the internal antenna to be broadcasted inside the building.
The Internal Antenna
The internal antennal broadcasts the amplified signal to the cellular devices. It is good to use a monopole antenna as it equally distributes the cellular signal in all directions. But there are also directional antennas that broadcast signal in the direction it is pointed.
The Working Of A Cell Phone Repeater
The cellular signal from the outside antenna is sent through the duplex filter to the low noise amplifier (LNA). Passing through the filter slightly reduces the strength of the signal, and this is compensated by the LNA by providing enough strength, i.e. gain. This sufficiently boosted signal is then sent to the bandpass filter which selects the bandwidth in which the signal is to be boosted by the device. You should know that the required bandwidth is preset or manually selected by the end-user. Now, the selected signal is sent to the power amplifier module to be amplified in the required bandwidth. This amplified signal is finally sent to the duplex filter to separate low and high frequencies.
One of the advantages of having duplex filters is that it helps to avoid signal overload of the amplifier, and this happens when the cellular signal is strong. When such a signal is amplified, there will be significant noise in the output signal. The other advantage is that it helps to select the cellular signal from a particular carrier if signals from multiple carriers are picked up by the outside antenna of the cell phone repeater.
The cell phone repeater is a type of distributed antenna system (DAS), known as passive DAS. These devices are becoming popular among users as they are a cost-effective solution to improve cellular network coverage.