More abp
UPGRADING FROM 2G/3G FOR TELKOM BASE STATIONS TO LTE
LTE stands for long term evolution
To increase Broadband capacity
To increase processing speed to get the fastest Internet with the network.
Basic Theoretical background
BBU
Telkom base stations is mainly using BBU3900 or BBU3910.BBU stands for Base Band Unit.Base band unit refers to original signal or unmodulated signals that is signals which occupy the lowest range of frequency. BBU processes these signals of original frequency before it is modulated(modulation is the addition of information to an electronic or optical carrier signal while carrier signal is the one with a steady waveform with constant height pitch and frequency.)
In Base band unit ifrequency is not shifted to some other frequency band by means of modulation.
BBU have DSP (digital signal processor) that processed the conversion between analog and digital signals.It is known as the heart of communication because it serves for communication link between two ends.
BBU along with RRU( Radio Remote Unit) formed as BTS.BTS stands for Base Transceiver station .In short RRU process the incoming radio signals and sends signals,receives signals from the antenna EM waves through hollow guided jumpers.
BBu is connected with RRU Thru CPRI(Common Public Radio fibre cable for making BTS.
FUNCTIONS OF BBU
provide common public radio interface CPRI ports or optical link for communication with RRU and process uplink and downlink baseband signals.
provides S1 Ports for communication between E -UTRAN node B( enodeB and an MME/S-GW and X2 port for communication between enodes Bs
Provides clock ports fort clock synchronisation, alarm monitoring, port for environment monitoring and universal serial BUS (USB) ports for commissioning using USB flash drives
Manages the eNode B through the operation and Maintainance and signal message processing.
BBU consist of the following ,FAN,LBBP,UMPT,LIPEU and other empty slots where necessary additional control cards can be slotted for needed operation a brief description of each is given below:
FAN
The fan dissipates heat from BBU 3900.It monitors the inlet temperatures and controls the rotation speed of the fans and report the status of fans to the LMPT or UMPT in BBU 3900
LBBP
This stands for LTE Base band Processing unit.Huawei 3900 series have 3 different LBBP:LBBPa,LBBPb,LBBPc,but in Huawei 3910 LBBP is termed UBBP.LBBP &UBBP main difference is that LBBP is for LTE or 4G Communication while UBBP is for 2 G and 3 G communication. UBBP also have 3 types 1 to 3
Both LBBP and UBBP functions to: (1) Provide CPRI port for communication with Radio Frequencies(R.F modules).
(2)Processes uplink and downlink baseband signals.
UMPT
UMPT stands for universal main procession and transmission unit and its functions are as follows:
1.Mainly performs OM functions including configuration,management equipment, management performance, monitoring, signal processing and active standby switchover.
2.Provides clock reference,transmission ports and maintenance link connecting to OMC.The OMC can be LMT(local maintenance terminal) or M2000 client.
TYPES OF UMPT
All UMPT have the same appearance on the upper left of the UMPT panel there is a silkseree UMPT and on the lower left of UMPT panel there is a label indicating type of UMPT Board. The Base station need is supported by I.P sec and PKI.
When the site is configured with UMPT a2 and a NodeB needs to be added at the site,the existing UMPT a2 can be used as the Main control board of Newly added node B.
If the site requires a GPS reference clock a USCU is prefentially configured.
When a site is configured with UMPT a1 and LTE FDD base station need to be added at the site, the existing UMPT a1 can be used as the main control board of newly added LTE.
When base station need to be converted to support multiple nodes including LTE TDD a UMPT2 must be configured.
When each mode in multimode base station needs to meet preceeding requirements for GSM,UMTS,LTE, FDD,LTE TDD a UMPTb1 is required.
How to determine the working mode of UMPT indicators R0, R1,R2 on the UMPT panel are used to determine working mode of the UMPT board.
UMPT has a CI port which does not exist on other main control board used to achieve BBU interconnection through UCIU plus UMPT in The other BBU.
UMPT is connected to a computer to implement local BBU maintenance, the USB port on UMPT is used for connecting UMPT to a computer .To connect UMPT to a computer you do as follows: connect the USB connection at one end of USB to Ethernet cable to the USB port on the UMPT and connect at the other end of cable to the computer.
UMPT cannot be used as a spare to replace WMPT or LMPT.If LMPT or WMPT need to be replaced by UMPT software configuration need to be modified after the hardware replacement is complete. Interim of hard core operations of replacing WMPT with UMPT are the same as those of replacing WMPT with s new WMPT
UPEU
Stands for Universal power and environment interphase unit and its functions are:
1.converts power of - 48volts input into +12volts with 300watts and 650watts power needed for BBU operation and processing.
2.It takes EMUB signals through RS485 serial communication and convert Bolean signals. Thus act as an interphase unit for BBU and EMUB.EMUB is environment monitoring unit for sensors alarm.
BBU consist of GPS sensors which track BBU installed location and if BBU is stollen the GPS coordinates is traced and send back to the Telecom operator control room.
They are many BBU models manufactured by various telecom companies and top 5 are: Erickson, Alcatel-lucent,HuaweiTechnologies,Cisco systems, and ZTE corporation. These vendors have their own type BBU models though The basic knowledge is the same.The difference is that their power efficiency and processing as well as working speed.
RRUs
Stand for Remote Radio Unit
FUNCTIONS OF RRUs
Perform data processing, modulation, combination, and division of R.f signals sent to the antenna.
Receives R.f signals from the antenna and perform demodulation as well as amplification of A/D conversions,filtering the signals and sending the signals to BBU for further processing.
Process the Baseband signal for processing for GSM
Controls power
Provides detection voltage standing wave ratio(VSWR)
Provides power for tower mounted amplifiers (TMA) and control signals for RET antenna.
Generates CPRI clock signal and regenerates CPRI signals in The event of loss of synchronisation and perform detection alarm.
RRUs are amounted near Antenna which reduces Attenuation over feeder.Mounting RRU near antenna also improves BTS performance connection between RRU and BBU is done with fibre optical cable. For proper work on RRU need to be powdered by 48 volt D.c voltaLTE
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