Aileron Ltd specializes in OEM Aileron cell phone boosters and repeaters, that will improve your cell phone signal strength and coverage area. Available for GSM-900, DCS-1800, CDMA, 3G, 2100 MHz, both voice and data applications. Use our Aileron GSM repeaters and keep your cell phone online, your data applications running in your home, office, or a truck.
Our wide range of production: cellular repeater, cell phone repeater, or wireless cellular signal booster, a type of bi-directional amplifier, is a device used for boosting the cell phone reception to the local area by the usage of a reception antenna, a signal amplifier and an internal rebroadcast antenna. These are similar to the cellular broadcast towers used for broadcasting by the network providers, but are much smaller, usually intended for use in one building.
Modern cellular repeater amplifiers rebroadcast cellular signals inside the building. The systems usually use an external, directional antenna to collect the best cellular signal, which is then transmitted to an amplifier unit which amplifies the signal, and retransmits it locally, providing significantly improved signal strength.
The more advanced models often also allow multiple cell phones to use the same repeater at the same time, so are suitable for commercial as well as home use.
The market for cellular repeaters is expected to grow rapidly over the coming years, particularly in the USA. This is due to the combination of the poor network coverage in some areas, and the large scale departure from the land-line system.
One advantage of cellular repeaters is an increase in the cell phone's battery life due to the lower power required to broadcast the signal to the local bi-directional amplifier, due to its proximity to the phone.
External directional antenna
Although some of the less expensive models do not include an external directional antenna, they are crucial to providing significant signal strength gain. This is because the antenna can be oriented and located outside to provide the best possible signal, usually aligned with the nearest cell tower. Generally speaking the larger the external antenna the better the signal - although even a small, correctly oriented external antenna should provide better signal than the internal antenna on any cell phone. These can either be fitted by professionals or will include a signal strength monitor for easy alignment.
Internal rebroadcast antenna
The better systems will generally include an internal monopole antenna (although the type of antenna is far from standardized) for rebroadcasting the signal internally - the advantage of using a monopole antenna is that the signal will be equally distributed in all directions (subject, of course, to attenuation from obstacles). Because all radio antennas are intrinsically polarized, cell phones perform best when their antennas are oriented parallel to the booster's antenna - although within reasonable proximity the booster's signal will be strong enough that the orientation of the cell phone's antenna will not make a significant difference in usability.
All models will include a signal amplifier. Even the cheaper home-use models (typically band selective) now provide 20 dB - 75 dB gain and many of the more expensive models provide over 50 dB. Excellent high-power models (not home usage - smart and expensive technology of the operators) offering gain around 100 dBm (ICE function is welcomed as an improvement of the radio isolation between donor and service antenna). However, since the decibel scale is measured on a logarithmic scale a 30 dB gain represents a one thousandfold signal power increase - meaning the total amplification of a repeater with greater than around 50 dB is likely to be useless without a good, well aligned antenna. This is due to the difficulty of filtering the correct signal out from the background noise, which will be amplified equally, and the limiting maximum signal power of the amplifier (for picorepeaters typically from around 5 dBm (3.2 mW)).
Standard GSM channel selective repeater (operated by telecommunication operators for coverage of large areas and big buildings) has output power around 2 W, high power repeaters (e.g., NodeG from Andrew) offering output power around 10 W). The power gain is calculated by the following equation: For repeater is needed to secure sufficient isolation between donor and service antenna. When the isolation is lower than actual gain + reserve (typically 5-15 dB) then repeaters is in loop oscillation.
Also cheap models are equipped by automatic gain reduction in case of poor or weak isolation. In case of poor isolation the device works but with low gain, and coverage is poor. The isolation is possible to improve by antenna type selection, in macro environment by angle between donor and service antenna (ideally 180°), space separation (typically vertical distance in case of the tower installation between donor and service antenna is several meters), inserting of the attenuating environment (smart placement of the donor and service antenna, e.g., between donor and service antenna is wall, placement of the metal mesh), reduction of reflections - in front of the donor antenna no near obstacle (like tree, metal-sheet building, glasshouse, or house)).
Isolation can be also improved by integrated feature called ICE (interference cancellation equipment) offered in some products. Activating of this feature has negative impact to internal delay (higher delay => prox. +5us up to standard rep. delay) and consequently to shorter radius from donor site, where could be repeater used. By amplification and filtration there is some delay (typically between 5us to 15us). It depends on the type of repeater and used features.
Additional delay form point of view of propagation means additional distance. Because of the cellular network has form principle reduced cell size (depends on the technology and activated features typically X*10 km (for standard GSM 35 km), urban FDD/TDD network 20 km) usage of repeater virtually moving user to bigger distance: radio distance = real distance + (repeater delay in us) *0.3 km (delay of RF signal in air is 3.3us/km). It is reason why somewhere with sufficient levels repeater doesn't work. After repeating you have better (or excellent) coverage but you can't access to network. User is from network point of view too far.
Reasons for weak signal
In many rural areas the housing density is too low to make construction of a new base station commercially viable. In these cases it is unlikely that the service provider will do anything to improve reception, due to the high cost of erecting a new tower. As a result, the only way to obtain strong cell phone signal in these areas is usually to install a home cellular repeater. In flat rural areas the signal is unlikely to suffer from multipath interference, so will just be heavily attenuated by the distance. In these cases the installation of a cellular repeater will generally massively increase signal strength just due to the amplifier, even a great distance from the broadcast towers.
Building construction material
Some construction materials very rapidly attenuate cell phone signal strength. Older buildings, such as churches, which use lead in their roofing material will very effectively block any signal. Any building which has a significant thickness of concrete or amount of metal used in its production will attenuate the signal. Concrete floors are often poured onto a metal pan which completely blocks most radio signals. Some solid foam insulation and some fiberglass insulation used in roofs or exterior walls has foil backing, which can reduce transmittance. Energy efficient windows and metal window screens are also very effective at blocking radio signals. Some materials have peaks in their absorption spectra which massively decrease signal strength.
Large buildings, such as warehouses, hospitals and factories, often have no cellular reception further than a few meters from the outside wall. Low signal strength is also often the case in underground areas such as basements and in shops and restaurants located towards the centre of shopping malls. This is caused by both the fact that the signal is attenuated heavily as it enters the building and the interference as the signal is reflected by the objects inside the building. For this reason in these cases an external antenna is usually desirable.
Even in urban areas which usually have strong cellular signals throughout, there are often dead zones caused by destructive interference of waves which have taken different paths (caused by the signal bouncing off buildings etc.) These usually have an area of a few blocks and will usually only affect one of the two frequency ranges used by cell phones. This is because the different wavelengths of the different frequencies interfere destructively at different points. Directional antennas are very helpful at overcoming this since they can be placed at points of constructive interference and aligned so as not to receive the destructive signal. See Multipath interference for more.
Diffraction and general attenuation
The longer wavelengths have the advantage of being able to diffract to a greater degree so are less reliant on line of sight to obtain a good signal, but still attenuate significantly. Because the frequencies which cell phones use are too high to reflect off the ionosphere as shortwave radio waves do, cell phone waves cannot travel via the ionosphere.
Different operating frequencies
Repeaters are available for all the different GSM frequency bands, some repeaters will handle different types of network such as multi-mode GSM and UMTS repeaters however dual- and tri-band systems cost significantly more.
Repeater systems are available for certain Satellite phone systems, allowing the sat phones to be used indoors without a clear line of sight to the satellite.
Please feel free to contact us with any inquiries, we will do our best to help you.