It’s not a Shabaab watch tower, it’s a Base Transceiver Station

Several people have been wondering about the white tower being erected in the university (Dedan Kimathi University of Technology). Due to current wave of terrorist attack, others think it’s a Shabaab watch tower. One school of though is for this: “The University have heightened security at all the gates, but they are not stopping at that, they have set this to help see the Shabaab from a long range”. Well that isn’t true. So what is it?

The cellular tower is a temporary telecommunication infrastructure that will facilitate (boost) wireless communication between a subscriber device/equipment or operator devices and a telecom operator network (Safaricom) during the beatification of Sister Irene Stefani. Thousands of people are expected to grace the event. User equipment are devices like mobile phones, wireless internet devices while operator devices are devices such as GSM(Global System for Mobile Communications), Code Division Multiple Access (CDMA) ,TDMA platform, Wi-Fi and WiMAX  (Worldwide Interoperability for Microwave Access)  among others.

The entire base station consist of a cellular tower and a BTS, also known as a base station (BS), radio base station (RBS) or node B (eNB). Most people confuse the tower and the entire base station to be the BTS.

This is the Base Transceiver Station (BTS)

The BTS comprises of a fix radio Transceiver (TRX) which handles transmission and reception of signals; sending and reception of signals to or from higher network entities, a Combiner which Combines feeds from several TRXs so that they could be sent out through a single antenna thus reducing the number of antennas that need be installed, a Power amplifier which aids in signal amplification from TRX for transmission through the antenna, a Duplexer which is used for separating, sending and receiving signals to or from the antenna and an Antenna which is an external part of the BTS

The temporary station receives a signal from a parent base station controller (BSC) at Kamakwa through the dish. A BTS is usually placed in the center of a cell serving as a single cell. It is assigned a Cell Identity. The cell identity is 16-bit number (double octet) that identifies that cell in a particular Location Area.

 In a typical structure, there are three sectors served by separate antennas. Each sector has a separate direction of tracking, typically of 120° sector of an area with respect to the adjacent ones .Usually a tower with 3 BTSs will accommodate all 360 degrees around the tower, however, depending on geography and user demand of an area, other orientations may be used including orienting the antennas to serving sectors of 180° separation to one another.

The BTS equipment are usually housed in a shelter which protects the telecoms equipment from external conditions such as dust, corrosion, rust or even theft.

On the cellular tower, we have remote radio unit (RRU), 2G, 3G and the Antenna. The RRU include a cyclic prefix (CP) module with a CP adder for downlink channel processing and a CP remover for uplink channel processing. The RRU can be configured to communicate with a base band unit (BBU) via a physical communication link and can communicate with a wireless mobile device via an air interface.

Sitting on the antenna and pointing at the RRU. All of them are lifted to the cellular tower .They will be  bolted to the H-frame.

On health risks, there is no substantial link between exposure to electromagnetic signals at the level of BTS and mobile telephone handsets transmission.