RF Module operation and main blocks The RF Module is a stand-alone fully operational transceiver module with integrated antenna filters. The RF Module is able to support one to three sectors in a Flexi Multiradio WCDMA base station. The RF Module hosts the RF functionality and provides control and power supply to the Flexi Antenna Line. Radio-related signal processing is performed in the RF Module. The RF Module has integrated fans and Bias-Ts. RF Module types available: • 3-sector RF Module • Dual RF Module • Single RF Module For detailed information on delivery contents, see Contents of the RF Module delivery. Incorrect cables and seals may not provide secured weather protection. In outdoor installations, including the outdoor cabinet, use only tested, at least IP55 class outdoor antenna jumper cables provided by Nokia Siemens Networks. This is also recommended for indoor installations. The following versions of the RF Module are available: Version Description FRIA Dual 50 W 1700/2100 FRIB Single 50 W 1700/2100 FRGC Dual 50 W 2100 FRGD Single 50 W 2100 FRGJ Dual 50 W 2100 FRGK Single 50 W 2100 FRGL Dual 50 W 2100 FRGM Single 50 W 2100 FRCA Dual 50 W 850 FRCB Single 50 W 850 FRDA Dual 50 W 900 FRDB Single 50 W 900 FRFA Dual 50 W 1900 FRFB Single 50 W 1900 FRGF Flexi 3-sector RF Module 2100 FRKA Flexi 3-sector RF Module 1500 FRGP Flexi 3-sector RF Module 2100 FRIE Flexi 3-sector RF Module 1700/2100 FXDA Flexi 3-sector RF Module 900
Version Description FXCA Flexi 3-sector RF Module 850 FXEA Flexi 3-sector RF Module 1800 Table 1: RF Module versions RF Module operation See the following figures for exploded views of the RF Module.
Figure 1:
Exploded view of the 3-sector RF Module
Figure 2: Exploded view of the RF Module (Dual) The RF Module can support one to three sectors with the following integrated components: • Transceivers with TX for two to four carriers (three transceivers in the 3-sector RF Module, two in the Dual and one in the Single RF Module) • Transceivers with RX for two to four carriers with diversity (the carriers must be adjacent) (three transceivers in the 3-sector RF Module, two in the Dual and one in the Single RF Module) • Linear power amplifiers (three in the 3-sector RF Module, two in the Dual and one in the Single RF Module) • RF filters with main and div branch (three in the 3-sector RF Module, two in the Dual and one in the Single RF Module) • 48 V DC input power supply • Masthead amplifier and 3GPP Antenna tilt power feed and control for up to three sectors
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Interface to the System Module Interface for chaining System Modules (3-sector RF Module only) Integrated fan assembly (two fans) Full operational bandwidth support Antenna connector interfaces Prepared for AISG2.0
The 3-sector RF Module has three independent transceivers each composed of one transmitter chain and two independent uplink chains to implement uplink diversity. The unit integrates an antenna filter unit that contains three filter blocks, each composed of one duplex filter (main antenna) and RX filter (diversity antenna), providing six antenna connectors for the BTS antenna line. The transceivers can be configured independently to dual or single carrier modes. The Dual RF Module has four dual carrier receivers that facilitate two dual carrier receivers with 2-way uplink diversity and it can therefore support multiple configurations. The Single RF Module is a half capacity version of the Dual RF Module. It has one TX/RX output that supports a maximum of two TX carriers (two carriers per TX chain). There is one RX output connector as well. FRGF, FXC FRGP, FRIE, FXDA, FXEA FRKA A # carriers 2 3 4 Table 2: Number of carriers supported by 3-sector RF Modules The RF Module uses nominal 48 V DC for internal power supply. The FRGD can also use nominal 100/240 V AC (optional unit), which increases the power consumption by approximately 10 %. The main and diversity branches include Bias-Ts with lightning strike protectors (Single and Dual RF Module). The main branch (Tx/Rx) Bias-T is used for Flexi Antenna Line and MHA support. It supports Current Window Alarm (CWA) mode, and 3GPP and AISG 2.0 interfaces (the FRGG, FRGF, FRGP, FRGJ, and FRGK also support the proprietary AISG1.1 interface for NBxx replacements). The diversity (Div Rx) branch Bias-T is only used for MHA support in Current Window Alarm (CWA) mode. The main branch also includes an Antenna Line VSWR Monitor (power meter for forward and reflected voltage ratio measuring). The operating voltages fed via main antenna line are 0 V DC/+12 V DC/+28.5 V DC and via diversity antenna line 0 V DC/+12 V DC.
The VSWR monitoring system is used for producing alarms for the antenna line condition against alarm threshold (RRH, Single, Dual and 3-sector RF Module). As a default setting, the minor alarm will be generated when the VSWR is 1.9 and major alarm (cell down) will be generated when the VSWR is 2.6. However, it is possible to adjust both minor and major alarm threshold between 1.5-3.5. The antenna line does not provide any alarms without a valid licence (Line Supervision RAN907LK). AISG1.1 RET Antenna Line Device configuration is supported with the FRGG, FRGF, FRGP, FRGJ, and FRGK. Flexi RF Module has 4.2MHz wide filtering in the receiver side. 4.2 MHz filtering reduces uplink interference from adjacent systems (such as GSM) and enables WCDMA deployment in less than 5 MHz in frequency refarming cases. The 4.2 MHz fixed filtering has been implemented in 900 MHz products (WN4.0), 850 MHz products (WN5.0), 1900 products (WN5.0 CD3) and 1800 products (WN6.0 EP1). RF bandwidths for the RF Module See the following table for RF bandwidths. Version RF bandwidth FRGF TX: 10 MHz RX: 20 MHz FRGP TX: 20 MHz RX: 20 MHz FRIE TX: 20 MHz RX: 45 MHz FXDA TX: 20 MHz RX: 20 MHz FXCA TX: 15 MHz RX: 15 MHz FXEA TX: 20 MHz RX: 30 MHz FRKA TX: 10 MHz RX: 10 MHz Table 3: RF bandwidths for 3-sector RF Modules Functional blocks The RF Module includes the following functional blocks: • RF control block: There are interfaces from the RF control block towards the System Module through optical connection. Most unit internal connections are made from the RF control block. Signal processing and unit control functionalities are located in this block.
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TX block: Analogue RF parts are located in the TX block. PA block: The power amplifier block amplifies TX block output signal to a specified output power level. RX block: In dual version, the RX block includes four 2-carrier receivers and in Single RF Module two 2-carrier receivers. In 3sector RF Modules, the RX block includes six 4-carrier receivers. Antenna filter block: Antenna filtering for TX and RX signals is done in the Antenna filter block.
In the Single version, there is only one TX block, PA block and Antenna filter block. In the RX block, only half of the blocks components are installed. RF Module versions FRGF, FRGP, FRGJ and FRGK support 2100 MHz band with high gain MHA. The FRGJ and FRGK can be used with NBxx replacements having 24 dB TMA installation, thus existing TMAs can be utilised. The FRGF, FRGP, FRGJ and FRGK support 2100 MHz band with high gain MHA from 0 dB to 33 dB. See the following figures for the functional blocks of the RF Module.
Figure 3:
Functional blocks of the 3-sector RF Module
* Not applicable to FRGF ** Not applicable to FRGF and FRKA
Figure 4: Functional blocks of the Dual RF Module (FRIA, FRGJ, FRCA, FRDA, FRFA) The FRGC/L have fixed LNA gain.
Figure 5: Functional blocks of the Single RF Module (FRIB, FRGK, FRCB, FRDB, FRFB
