Nokia Siemens Networks Flexi WCDMA Teardown: Antenna (part 3 of 3)

Nokia Siemens Networks Flexi Multiradio BTS is a GSM/EDGE, WCDMA/(I-)HSPA, and LTE base station. Used in mobile telecommunication antenna networks. A network that you use daily on your cellphone.

Part 1: System station and Part 2: Power amplifier

Phased Antenna Array

This is an obsolete Kathrein XPol 2-port single band panel antenna. The 2 ports means that it actually has 2 antennas in the one unit. There is a main and a diversity antenna (90° polarized to each other) for 1710 – 2200 MHz (1800-2100 MHz mobile bands).

Newer antennas now have to allow for 700 LTE, 850 UMTS, 900 GSM and UMTS, 1800 LTE/GSM, 2100 UMTS and 2300 LTE. New antennas have considerably more different elements inside of them.

Each of the two antennas consists of a co-phased stacked array of dipoles. There is a total of 8 dipole pairs per antenna.

The antenna housing also includes a RET (Remote Electrical Tilt) function. This allows for adjusting the direction of the electromagnetic lobe, without climbing the tower or even moving the panel. By using a phase shifter located on the backside of the antenna. The lower elements are phase-delayed to electrically drop the front lobe down, without physically tilting the panel.

The phase shifters are actuated via the white glass fiber rod running up the side of the front of the antenna. The position of the arm inside the phase shifter is adjusted by turning the screw mechanism next to the connectors.

Specifications

Frequency bands: 700, 800, 850, 900, 1800, 1900, 1700/2100, 2100, 2300 and 2600 MHz.

Maximum capacity: Up to 6+6+6 GSM or 4+4+4 WCDMA or 1+1+1 LTE at 20 MHz or flexible combination of the above technologies in concurrent mode.

Multi-radio configuration: 1 Flexi 3-sector RF module + 1 system module for GSM/EDGE + 1 system module for WCDMA/HSPA and LTE. Remote Radio Head (RRH) solution also supported.

RF power amplifier technology: Multicarrier power amplifier (multi-standard)

Height x width x depth: 133 x 447 x 560 mm per module, indoors and outdoors. Fits in any 19” rack.

Weight: 25 kg per module

Operating temperature range: -35 °C to +55 °C

Power supply: 40.5 – 57 VDC, 184 – 276 VAC with power module

Typical power consumption: 790W for combined GSM and WCDMA site

Output power: 240 W per RF module or 40 W + 40W per Remote Radio Head (RRH)

Ingress protection class: IP 65