Nortel Networks Welding System 411 2021 111 User Manual

411-2021-111  
Wireless Networks  
DualMode Metrocell  
Cell Site Description  
411-2021-111 Standard 01.01 June 1996  
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Wireless Networks  
DualMode Metrocell  
Cell Site Description  
Product release: DualMode Metrocell  
Document release: Standard 01.01  
Date: June 1996  
Document Number: 411-2021-111  
Copyright Country of printing Confidentiality Legal statements Trademarks  
1996 Northern Telecom  
Printed in the United States of America  
NORTHERN TELECOM CONFIDENTIAL: The information contained in this document is the property of Northern  
Telecom. Except as specifically authorized in writing by Northern Telecom, the holder of this document shall keep the information  
contained herein confidential and shall protect same in whole or in part from disclosure and dissemination to third parties and use  
same for evaluation, operation, and maintenance purposes only.  
Information is subject to change without notice.  
DMS, DMS SuperNode, DMS-MSC, DMS-HLR, DMS-100, and MAP are trademarks of Northern Telecom.  
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iv  
Publication history  
June 1996  
Standard 01.01  
Initial release of document.  
411-2021-111 Standard 01.01 June 1996  
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v
Contents  
Publication history  
iv  
ix  
About this document  
Intended audience for this publication ix  
How this publication is organized x  
Applicability of this publication x  
List of terms  
xi  
Introduction  
1-1  
Northern Telecom's DualMode Metrocell 1-1  
The 800 MHz cellular band 1-4  
Cell Site Configurations  
Overview 2-1  
Omni configuration 2-1  
120° sectorized configuration 2-2  
60° sectorized configuration 2-4  
2-1  
3-1  
Cell Site Layouts  
Omni cell site configuration 3-1  
Control Channel redundancy 3-2  
Transmit cabling 3-5  
Receive cabling 3-7  
Component requirement 3-7  
120° STSR cell site configuration 3-8  
Control Channel redundancy 3-8  
Transmit cabling 3-12  
Receive cabling 3-17  
Component requirement 3-20  
60° STSR cell site connection 3-21  
Control Channel redundancy 3-21  
Transmit cabling 3-27  
Receive cabling 3-33  
Component requirement 3-37  
DMS-MTX DualMode Metrocell Cell Site Description  
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vi Contents  
Cell Site Components  
Customer Service Operations 4-3  
4-1  
5-1  
Power and Grounding Requirements  
Safety requirements 5-1  
Power and grounding requirements 5-2  
Frame power distribution 5-5  
System power protection 5-6  
Grounding 5-6  
Cable Identification 5-9  
Datafilling a Metro Cell Site  
Datafill Overview 6-1  
6-1  
Table CLLI 6-2  
Table ACUALM 6-2  
Table VCHINV, CCHINV, LCRINV 6-5  
Appendices  
Appendix A: DualMode Metrocell Cell Site Specifications 7-1  
System Configuration 7-1  
Radio Frequency 7-1  
Audio Interface 7-2  
Alarms 7-2  
DC Power Requirements 7-3  
Power Distribution Requirements 7-3  
Mechanical 7-3  
Packaging 7-4  
Environmental 7-4  
Regulatory 7-5  
Appendix B: Frequency plans 7-7  
N=7 Frequency plan (Band A) 7-7  
N=7 Frequency plan (Band B) 7-8  
N=4 Frequency plan (Band A) 7-9  
N=4 Frequency plan (Band B) 7-9  
List of figures  
Figure 1-1  
Figure 1-2  
Figure 1-3  
Figure 1-4  
Figure 2-1  
Figure 2-2  
Figure 2-3  
Figure 3-1  
System architecture of a DualMode Metrocell 1-2  
Digital ready cellular product 1-2  
Basic components of a DualMode Metrocell 1-3  
Channel assignment for 800 MHz cellular systems 1-4  
Omni (N=7) frequency reuse plan 2-2  
120° (N=7) sectorized frequency reuse plan 2-3  
60° (N=4) sectorized frequency reuse plan 2-4  
Frame layout of an omni Metrocell with one RF frame (front view) 3-  
2
Figure 3-2  
Figure 3-3  
Block diagram of an omni Metrocell with up to 20 channels in one  
RF Frame 3-3  
Block diagram of an omni Metrocell with 21 to 24 channels in one  
RF Frame 3-4  
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Contents vii  
Figure 3-4  
Figure 3-5  
Frame layout of a 120° STSR Metrocell site with one RF frame  
(front view) 3-9  
Frame layout of a 120° STSR Metrocell site with three RF frames  
(front view) 3-9  
Figure 3-6  
Figure 3-7  
Block diagram of a 120° STSR Metrocell using one RF Frame 3-10  
Block diagram of a 120° STSR Metrocell using three RF Frames 3-  
11  
Figure 3-8  
Figure 3-9  
Frame layout of a 60° STSR Metrocell with two RF frames (front  
view) 3-22  
Typical frame layout of a 60° STSR Metrocell with four RF frames  
(front view) 3-22  
Figure 3-10  
Figure 3-11  
Figure 5-1  
Figure 6-1  
Figure 6-2  
Block diagram of a 60° STSR Metrocell with two RF Frames 3-23  
Block diagram of a 60° STSR Metrocell with four RF Frames 3-25  
Power distribution for the CE and RF Frames in a Metrocell 5-5  
Example of Metro TRU datafill 6-6  
Example of Metro ICRM/TRU hardwire configuration 6-7  
List of tables  
Table 1-1  
Table 3-1  
Channel designation and frequency assignment 1-5  
RF Frame 1 PA to ATC connection for an omni Metrocell with up to  
20 channels 3-5  
Table 3-2  
RF Frame 1 PA to ATC connection for an omni Metrocell with 21  
channels or more 3-6  
Table 3-3  
Table 3-4  
Table 3-5  
Table 3-6  
RMC to splitter connections for an Omni Metrocell 3-7  
Component requirement for an omni Metrocell 3-7  
PA to ATC connection for a 120° Metrocell with one RF Frame 3-12  
PA to ATC connection for a 120° Metrocell with 20 channels or less  
per RF frame for one sector 3-13  
Table 3-7  
Table 3-8  
Table 3-9  
Table 3-10  
Table 3-11  
Table 3-12  
Table 3-13  
Table 3-14  
Table 3-15  
Table 3-16  
Table 3-17  
PA to ATC connection for a 120° Metrocell with 21 channels or  
more per RF frame for one sector 3-15  
RMC to splitter connections for a 120° STSR Metrocell with one RF  
Frame 3-17  
RMC to splitter connections for a 120° STSR Metrocell with three  
RF Frames 3-18  
Component requirement for a 120° STSR Metrocell with one RF  
Frame 3-20  
Component requirement for a 120° STSR Metrocell with three RF  
Frames 3-20  
PA to ATC connection for a 60° STSR Metrocell using two RF  
Frames 3-28  
PA to ATC connection for a 60° STSR Metrocell using four RF  
Frames 3-30  
RMC to splitter connections for a 60° STSR Metrocell with two RF  
Frames 3-33  
RMC to splitter connections for a 60° STSR Metrocell with four RF  
Frames 3-34  
Component requirement for a 60° STSR Metrocell with two RF  
Frames 3-37  
Component requirement for a 60° STSR Metrocell with four RF  
Frames 3-37  
DMS-MTX DualMode Metrocell Cell Site Description  
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viii Contents  
Table 4-1  
Table 5-1  
Table 5-2  
Table 6-1  
Table 6-2  
Table 6-3  
Table 6-4  
Table 6-5  
Major components of a DualMode Metrocell 4-1  
Metrocell DC Power performance requirements 5-3  
Cable identification - North America 5-9  
Datafill differences of the Metrocell from an NT800DR cell 6-1  
Trunk requirement for different Metrocell configurations 6-2  
MTX Datafill Alarm Points for Metro RF Frame 6-3  
MTX Alarm Points Datafill Numbers for Metro RF Frame 6-4  
MTX Alarm Points Datafill Numbers for Metro CE Frame  
components 6-4  
Table 6-6  
NT8X47BA Port Numbers for Metro TRU locations 6-5  
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ix  
About this document  
This publication is one of a set of documents that provide Northern Telecom  
(Nortel) customers with information and suggestions on the planning and  
maintenance of their DualMode Metrocell system. This set of documents  
includes the following manuals:  
DualMode Metrocell Functional Description Manual  
— DualMode Metrocell Cell Site Description  
— DualMode Metrocell Common Equipment (CE) Frame Description  
— DualMode Metrocell Radio Frequency (RF) Frame Description  
DualMode Metrocell Planning and Engineering Guidelines  
DualMode Metrocell Installation Manual  
DualMode Metrocell Operation and Maintenance Manual  
DualMode Metrocell Troubleshooting Guidelines  
The manual suite for the DualMode Metrocell provides information on cell  
site configurations, hardware components, planning and installation  
procedures, as well as maintenance and troubleshooting methods.  
Intended audience for this publication  
The intended audience for this set of manuals is the cell site technicians and  
the planning engineers who require information in the maintenance and  
planning of a DualMode Metrocell. The Functional Description Manual  
provides a technical reference foundation for the other documents in the  
documentation suite and is written for all.  
The Planning and Engineering Guidelines is written for system planning  
personnel in implementing new cells or expanding existing cell sites in a  
cellular system.  
The Operation and Maintenance Manual and the Troubleshooting Guidelines  
that provide information on problem recognition and preventive maintenance  
are written for cell site technicians to assist them in troubleshooting and  
performing their routine work.  
DMS-MTX DualMode Metrocell Cell Site Description  
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x About this document  
The document suite assumes that the reader possesses a basic knowledge of  
the cellular system and radio propagation and is familiar with measurement  
units incorporated in the system. Therefore, this document will not provide  
detailed information on the theory of switching and radio propagation.  
How this publication is organized  
This publication is organized to present the following information:  
an introduction to the DualMode Metrocell Cell Site  
the Metrocell cell site configurations; omni, 120° STSR and 60° STSR  
the equipment layouts, block diagrams and transmit and receive cabling  
for each configuration  
the cell site components required for each configuration  
the power and grounding requirements for a Metrocell cell site  
information on datafilling a Metrocell.  
Applicability of this publication  
This publication is generically applicable to MTX01 feature functionality, yet  
captures some BCS-independent environment and implementation issues.  
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xi  
List of terms  
A-Band  
The lower 333 channels (Channel 1 - 333) of the cellular band, normally assigned  
to a non-wireline operator in the US and Canada.  
The Expanded Spectrum provides 83 more channels, 50 (Channel 667 - 716) in  
the A-Band and 33 (channel 991 - 1023) in the A"-Band.  
ACU  
Alarm Control Unit. A unit that provides discrete alarm monitoring, reporting and  
control functions at the cell site. It concentrates all alarm input points at the cell  
site and updates the MTX of any status change over redundant data links.  
AMPS  
ATC  
Advanced Mobile Phone Service. Analog cellular phone service.  
AutoTune Combiner. A cavity/isolator combiner featuring an automatic tuning  
system which monitors the transmitted RF and automatically tunes itself to that  
frequency.  
B-Band  
The upper 333 channels (Channel 334 - 666) of the cellular band, normally  
assigned to a wireline operator in the US and Canada.  
The Expanded Spectrum provides 83 more channels (Channel 717 - 799) in the  
B’-Band.  
BER  
Bit Error Rate. The ratio of error bits to the total number of transmitted bits. It is  
a measurement of quality of the digital connection.  
Carrier (RF)  
An unmodulated radio signal. Normally, it is a pure sine wave of steady  
frequency, amplitude, and phase.  
CCH  
Control Channel, sometimes referred to as the Signaling Channel which is always  
in use to enable call setup and registration.  
DMS-MTX DualMode Metrocell Cell Site Description  
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xii List of terms  
Cell  
By theoretical design, it is the geographical representation of the cellular  
coverage area or service area defining both the associated size and shape.  
CSM2  
dBm  
Cell Site Monitor 2. A unit that provides analog testing and monitoring  
capabilities at the cell site.  
Decibels above a milliwatt. Unit of power measurement popular in wireless  
telephony, general telephony, audio, and microwave.  
dBW  
DCC  
Decibels above a watt. Unit of measurement for radio power  
Digital Color Code. An identifying code associated with the control channel of  
the cellular base transmitter which is used to enhance call processing in the  
cellular infrastructure.  
DLR  
Digital Locate Receiver. The TDMA equivalent of the Locating Channel  
Receiver. See LCR.  
DMS-MTX  
DPA  
The acronym for Nortel's family of cellular switches: Digital Multiplex Switch -  
Mobile Transmission Exchange.  
Dual Power Amplifier. A module which contains two discrete power amplifiers  
that provide amplification of the RF signal for the two corresponding Transmit  
Receive Units (TRU) on the same TRU/DPA shelf.  
DRUM  
DualMode Radio Unit Monitor. A test and monitor unit capable of radio  
communications with any Voice Channel of the local Transmit Receive Units  
(TRU) in the digital mode.  
Duplexer  
A device that consists of two pass or pass/reject filters configured to provide a  
common output port for both transmit and receive frequencies.  
DVCC  
ES  
Digital Verification Color Code. The TDMA equivalent of DCC.  
Expanded Spectrum. The additional frequency spectrum assigned to the cellular  
band. The Expanded Spectrum in the A-Band consists of the A’-Band and the A"-  
Band while the B’-Band is the Expanded Spectrum for the B-Band. The  
Expanded Spectrum provides a total of 416 channels to each of the two bands.  
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List of terms xiii  
FDMA  
Filter  
FM  
Frequency Division Multiple Access. A frequency assignment arrangement  
whereby all users share the total frequency allotment and each frequency is  
assigned to a given user at access on a multiple user access basis.  
A frequency selective device which is tuned to pass some frequencies and  
attenuate others. Common filter types include high-pass, low pass, band-pass,  
and notch filters  
Frequency Modulation. A modulation technique that causes the frequency of the  
carrier to vary above and below its resting frequency; the rate of which is  
determined by the frequency of the modulating signal and the deviation of which  
is determined by the magnitude of the modulating signal.  
Forward path  
The path from cell site to cellular subscriber.  
HSMO  
High Stability Master Oscillator. A unit that provides a highly stable 4.8 MHz  
reference for synchronizing the Transmit Receive Unit (TRU).  
ICP  
Intelligent Cellular Peripheral. A switch site peripheral that provides an interface  
between the cell site and the switch. The ICP also oversees the operations of the  
cell site.  
ICRM  
IM  
Integrated Cellular Remote Module. A cell site peripheral that serves as an  
interface between the Intelligent Cellular Peripheral (ICP) and the radio  
transmission subsystems. The ICRM is designed to support both analog and  
digital Radio Frequency (RF) equipment.  
Intermodulation. A type of interaction between signals in a nonlinear medium  
which produces phantom signals at sum and difference frequencies. These  
phantom signals may interfere with reception of legitimate signals occupying the  
frequencies upon which they happen to fall.  
Isolation  
LCR  
The attenuation (expressed in dB) between any two signal or radiation points.  
Locating Channel Receiver. A radio receiver which is frequency agile and is used  
to measure and report the received signal strength, in dBm, of a channel.  
Loss  
A magnitude of attenuation, expressed in dB, for a given path between any two  
points.  
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xiv List of terms  
Modulation  
The process of placing information on an RF carrier. The modulation technique  
may involve changing the amplitude, frequency, or phase of the carrier  
determined by the modulation index.  
NES  
Non-expanded Spectrum. The frequency spectrum initially assigned to the  
cellular band. The Non-expanded Spectrum provides 333 channels to each of the  
two bands, the A-Band and the B-Band.  
Omni  
An antenna design which permits radiation in essentially all H-Plane azimuths.  
In cell sites, an Omni configuration means a single set of omni antennas is used  
for all channels.  
π/4 DQPSK  
Variation of Differential Quadrature Phase Shift Keying used in D_AMPS IS-54  
TDMA for improved spectral characteristics and phase resolution. Permissible  
phase changes are integral multiples of π/4 radians (45 degrees). π/4 is used to  
reduce the peak to root mean square ratio requirements for linear PAs.  
Return loss  
A logarithmic relationship of the incident signal to the reflected signal as  
expressed, in dB, by the following relationship:  
P
r
Return Loss = 10 log  
P
i
where Pi = incident power in watts  
Pr = reflected power in watts  
The strength of the signal, expressed in dB, reflected by a load back into a  
transmission line due to impedance mismatch. -14 dB corresponds to a VSWR of  
1.5:1.  
Reverse path  
The path from cellular subscriber terminal to cell site.  
RF  
Radio Frequency. Electromagnetic energy of the frequency range just above the  
audible frequencies and extending to visible light.  
RIP  
Rack Interface Panel. The RIP is the interface between the cell site power supply  
and the cell site equipment.  
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RMC  
RSSI  
Receive Multicoupler. A device for amplifying the input received from a single  
antenna and providing multiple outputs for a group of receivers.  
Received Signal Strength Indicator. A measurement of the received RF signal  
strength measured at the base station or the subscriber terminal. It is expressed in  
dBm.  
SAT  
Supervisory Audio Tone. A tone of 5970, 6000, or 6030 Hz which modulates the  
AMPS voice channel along with voice audio. It is generated by the cell site and  
is repeated by the mobile back to the cell site. The repeated SAT is checked by  
the cellular system to confirm the continuity of the complete RF path from the  
cell site to the subscriber terminal and back to the cell site.  
SCC  
SAT Color Code. The datafill values corresponding to the various SATs: 00 for  
5970 Hz, 01 for 6000 Hz, 10 for 6030 Hz.  
Sector  
A theoretical wedge-shaped part of the coverage area of one cell site, served by a  
specific group of directional antennas on specific channels.  
Sectorization  
A cell site configuration that consists of two or more sectors in which a different  
control and voice channel assignment is given for each sector. In this  
arrangement, the datafill and channel assignments for each sector are tailored to  
meet the system operational requirements, providing more flexibility in the cell  
site configuration compared to an omni configuration but with a decrease in  
trunking efficiency.  
Signal (RF)  
SINAD  
Radio frequency energy associated with a particular or desired frequency.  
A standard measurement of detected audio quality that is related to signal-to-  
noise plus distortion of the RF signal strength at the receiver input terminal. 12  
dB SINAD is the commonly used threshold for receiver sensitivity measurements  
to determine the weakest-practical analog RF input, in dBm, required by the  
receiver. A SINAD of 20 dB is considered good quality and defines the RF input  
level needed to fully quiet the receiver.  
S/N  
Signal-to-Noise ratio. The ratio of signal power to noise power on a radio  
channel.  
DMS-MTX DualMode Metrocell Cell Site Description  
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xvi List of terms  
ST  
Signaling Tone. In AMPS cellular, a 10 kHz tone transmitted on the Reverse  
Voice Channel (RVC) as a precursor to messaging activity, and for certain call-  
processing functions (acknowledgments, call termination). Presence of the tone  
mutes normal conversational audio.  
STSR  
TDMA  
Sectored-Transmit/Sectored-Receive. A cell configuration in which a different  
control and voice frequency assignment is designated for each sector. A  
directional antenna system is required for each sector.  
Time Division Multiple Access. A modulation and transmission format that  
allows a number of digital conversations (three in TDMA-3) to occur within the  
same Radio Frequency (RF) channel. Mobile units take turns transmitting/  
receiving data on specific time slots of a TDMA frame.  
TRU  
Transmit Receive Unit. The TRU is a Digital Signal Processing (DSP) based  
transceiver capable of two modes of operation, analog (AMPS) and digital  
(TDMA).  
VCH  
Voice Channel. A Radio Frequency (RF) channel used to transmit cellular voice  
conversations. The VCH is also an integral part of call setup, handoff, and  
disconnect.  
VSWR  
Voltage Standing Wave Ratio. A measure of the mismatch between the  
transmitter source impedance and the load impedance to which it is connected. It  
is defined by the following relationship:  
Reflected Power  
1 +  
Forward Power  
VSWR =  
Reflected Power  
1 -  
Forward Power  
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1-1  
1
Introduction  
Northern Telecom's DualMode Metrocell  
As cellular systems evolve to the digital format, service providers and mobile  
subscribers are confronted by a mixture of analog and digital technologies.  
Northern Telecom (Nortel)’s dual mode cellular product allows a smooth  
transition from analog to digital technology. It uses Time Division Multiple  
Access (TDMA) technology for digital systems and Advanced Mobile Phone  
Service (AMPS) technology for analog systems. This evolutionary strategy  
enables service providers to gradually upgrade their cellular systems to digital  
while providing support of existing analog equipment.  
The Nortel cellularsystemsupportingdual mode service includesthe following  
components:  
the DMS-MTX switch containing the Intelligent Cellular Peripheral (ICP)  
unit at the mobile switching office  
dual mode cell sites with the configurable DualMode Radio Units (DRU)  
on a Radio Frequency (RF) Frame and the Integrated Cellular Remote  
Module (ICRM), on a Common Equipment (CE) Frame at the cell site  
external and internal interface links.  
The Nortel DualMode Metrocell serves as the intelligent interface between a  
Digital Multiplex Switch - Mobile Telephone Exchange (DMS-MTX) and its  
registered cellular mobiles. It is a dual mode cell that works in both the analog  
(AMPS) mode and the digital (TDMA) mode.  
The Metrocell is designed for high density, small radius cells in areas where  
large traffic capacity is required. It can exist independently or it can be added  
to existing cells for increased coverage. The Metrocell provides a reduced  
power output for urban applications. The typical power output of the Power  
Amplifier (PA) is 22 watts (43.5 dBm).  
Figure 1-1 shows the architecture of a DualMode Metrocell system and  
Figure 1-2 is a block diagram of the product of the system.  
DMS-MTX DualMode Metrocell Cell Site Description  
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1-2 Introduction  
Figure 1-1  
System architecture of a DualMode Metrocell  
Trunk  
DMS-MTX  
PSTN  
Digital Transmission  
Facility  
DualMode  
Metrocell  
Figure 1-2  
Digital ready cellular product  
DMS - MTX  
DRU  
voice &  
control  
DRUM  
CSM2  
voice and  
control  
control  
ICRM  
ICP  
control  
ACU  
SWITCH SITE  
CELL SITE  
There are at least two equipment frames in a Metrocell, a Universal Common  
Equipment (CE) Frame and a Metro Radio Frequency (RF) Frame. The cell  
site can be expanded or sectorized by adding more Metro RF frames as traffic  
grows. The number of Metro RF frames is determined by the cell site  
configuration and the channel capacity. Figure 1-3 shows the frames and the  
components of a DualMode Metrocell.  
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Introduction 1-3  
Figure 1-3  
Basic components of a DualMode Metrocell  
Universal CE Frame  
Metro RF Frame  
RIP  
RIP  
Duplexer  
(one to three)  
DRUM  
ACU  
ATC  
HSMO  
CSM2  
TRU/DPA Shelf  
(TRUs & DPAs)  
Dual RMC  
(one to six)  
ATC  
TRU/DPA Shelf  
(TRUs & DPAs)  
ICRM  
ATC  
TRU/DPA Shelf  
(TRUs & DPAs)  
Blank Panel  
Base  
Base  
Legend:  
RIP  
Rack Interface Panel  
DRUM  
ACU  
HSMO  
CSM2  
RMC  
ICRM  
ATC  
DualMode Radio Unit Monitor  
Alarm Control Unit  
High Stability Master Oscillator  
Cell Site Monitor 2  
Receive Multicoupler  
Integrated Cellular Remote Module  
AutoTune Combiner  
TRU  
DPA  
Transmit Receive Unit  
Dual Power Amplifier  
DMS-MTX DualMode Metrocell Cell Site Description  
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1-4 Introduction  
The 800 MHz cellular band  
In an 800 MHz North American cellular system, a frequency spectrum of 50  
MHz is available for service. Operating from 824 to 894 MHz, including the  
expanded spectrum, the system conforms to the AMPS IS-54 protocol.  
Typically this range is divided into 832 radio frequency (RF) channelsT.he 832  
RF channels are divided into two bands,A and B. The two bands are identified  
as follows:  
Band A—for Non-Wireline Operators  
Band B—for Wireline Operators.  
Each frequency band has 416 RF channels. Of these 416 RF channels,  
typically 21 (depending on the frequency plan) are assigned as the Control  
Channels (CCH) and the remaining 395 are Voice Channels (VCH). See  
Figure 1-4 and Table 1-1.  
Figure 1-4  
Channel assignment for 800 MHz cellular systems  
Base Station Frequency (MHz)  
835  
RX 824 825  
TX 869 870  
835 846.5 849 851  
890 891.5 894 896  
A-Band CCH  
B-Band CCH  
880  
A"  
A
B
A'  
B'  
R
Band  
991 1  
1023  
333  
716  
799  
R=Reserved  
666  
Channel Number  
Channel assignment  
Band A (416 channels) Band B (416 channels)  
Control channels  
313 - 333 (21)  
688 - 708 (21)  
334 - 354 (21)  
737 - 757 (21)  
Optional—TDMA secondary  
control channels  
Voice channels  
001 - 312 (312)  
667 - 716 (50)  
991 - 1023 (33)  
355 - 666 (312)  
717 - 799 (83)  
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Introduction 1-5  
Table 1-1  
Channel designation and frequency assignment  
System  
Channel  
Cell site receive  
frequency (MHz)  
Cell site transmit  
frequency (MHz)  
Not used  
990  
824.010  
869.010  
A"  
A
991 - 1023  
1 - 333  
824.040 - 825.000  
825.030 - 834.990  
835.020 - 844.980  
845.010 - 846.480  
846.510 - 848.970  
869.040 - 870.000  
870.030 - 879.990  
880.020 - 889.980  
890.010 - 891.480  
891.510 - 893.970  
B
334 - 666  
667 - 716  
717 - 799  
A’  
B’  
The relationship between the channel number (N) and the frequency is:  
Channel number: 1 N 799  
Receiver frequency (in MHz) = 0.03N + 825.000  
Transmit frequency (in MHz) = 0.03N +870.000  
Channel number: 990 N 1023  
Receiver frequency (in MHz) = 0.03(N - 1023) + 825.000  
Transmit frequency (in MHz) = 0.03(N - 1023) + 870.000  
Both non-expanded and expanded spectrums are shown in Appendix B for the  
N=7 and N=4 frequency groups.  
Important  
For ALL Metrocell cell site configurations, the frequency  
plan used should have a minimum of 21 channel spacing  
(630 kHz) between the RF channels.  
DMS-MTX DualMode Metrocell Cell Site Description  
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1-6 Introduction  
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2-1  
2
Cell Site Configurations  
Overview  
The DualMode Metrocell can be configured in the following ways:  
Omni-directional transmit/receive  
120° Sectored Transmit Sectored Receive (STSR)  
60° Sectored Transmit Sectored Receive (STSR)  
The majority of systems may begin as Omni-directional to minimize startup  
costs. As the subscriber traffic increases, the Omni configuration may reach  
its maximum traffic capacity. At that time it will be necessary to provide  
additional capacity through expanded spectrum, 120 degree sectorization, 60  
degree sectorization, or frequency borrowing.  
It is important that the operator selects a frequency plan before the Omni  
configuration is installed. If not, future expansions will be very difficult. The  
most common frequency plans are:  
7 Cell Cluster (N=7)—This frequency plan allows proper expansion from  
Omni to 120 degree sectorization (see Figure 2-1 and Figure 2-2).  
4 or 12 Cell Cluster (N=4 or N=12)—This frequency plan allows proper  
expansion from Omni to 60 degree sectorization (see Figure 2-3).  
Both non-expanded and expanded spectrums are shown in Appendix B for the  
N=7 and N=4 frequency groups.  
Omni configuration  
In an Omni (N=7) configuration, the 416 RF channels are divided among a  
group of seven cells (often known as a cluster). Each cell consists of a  
maximum of 59 or 60 RF channels (four cells with 59 channels and three cells  
with 60 channels, where three of the 59 or 60 channels are Control channels).  
The RF channels are reused by other cell clusters. Frequency reuse refers to  
the use of RF channels on the same carrier frequency in different areas which  
are separated from one another by the greatest possible distance so that co-  
channel interference is minimized.  
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2-2 Cell Site Configurations  
Figure 2-1 shows the layout of an Omni (N=7) frequency reuse plan;. The RF  
channels used in Cell 1 of a cluster are reused in Cell 1 of other clusters,  
channels in Cell 2 are reused in Cell 2 of other clusters and so on.  
Figure 2-1  
Omni (N=7) frequency reuse plan  
CELL 6  
CELL 5  
CELL 4  
CELL 6  
CELL 1  
CELL 3  
CELL 7  
CELL 2  
CELL 5  
CELL 4  
CELL 1  
CELL 6  
CELL 3  
CELL 7  
CELL 2  
CELL 7  
CELL 1  
CELL 2  
CELL 5  
CELL 4  
CELL 3  
120° sectorized configuration  
In a 120° (N=7) sectorized configuration, the 416 RF channels are divided  
among a cluster of seven cells. Each cell contains a maximum of 59 or 60 RF  
channels, with three Control channels for each cell. Since each cell is further  
divided into three sectors, each sector will contain a maximum of 19 or 20 RF  
channels, with one Control channel for each sector. The available RF  
channels are reused by other groups of cells within the system.  
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Cell Site Configurations 2-3  
Figure 2-2 shows the layout of a 120° (N=7) sectorized frequency reuse plan.  
The RF channels used in Cell 1 of a cluster are reused in Cell 1 of other  
clusters, channels in Cell 2 are reused in Cell 2 of other clusters and so on.  
This arrangement will have the RF channels using the same carrier frequency  
in different areas to be separated from one another by the greatest possible  
distance to minimize co-channel interference.  
However, sectorization (by virtue of the modified coverage areas and  
directional antenna usage) permits greater reuse of frequencies for a given  
C/I ratio.  
Figure 2-2  
120° (N=7) sectorized frequency reuse plan  
Sector  
X
Sector  
Z
CELL 6  
Sector  
X
Sector  
X
Sector  
Y
Sector  
Z
Sector  
Z
CELL 5  
CELL 7  
Sector  
X
Sector  
Y
Sector  
Y
Sector  
Z
CELL 1  
Sector  
X
Sector  
X
Sector  
Y
Sector  
Z
Sector  
Z
CELL 2  
CELL 4  
Sector  
X
Sector  
X
Sector  
Y
Sector  
Y
Sector  
Z
Sector  
Z
CELL 3  
CELL 6  
Sector  
X
Sector  
X
Sector  
X
Sector  
Y
Sector  
Y
Sector  
Z
Sector  
Z
Sector  
Z
CELL 6  
CELL 7  
CELL 5  
Sector  
X
Sector  
X
Sector  
X
Sector  
Y
Sector  
Y
Sector  
Y
Sector  
Z
Sector  
Z
Sector  
Z
CELL 5  
CELL 1  
CELL 7  
Sector  
X
Sector  
X
Sector  
X
Sector  
Y
Sector  
Y
Sector  
Y
Sector  
Z
Sector  
Z
Sector  
Z
CELL 1  
CELL 2  
CELL 4  
Sector  
X
Sector  
X
Sector  
X
Sector  
Y
Sector  
Y
Sector  
Y
Sector  
Z
Sector  
Z
Sector  
Z
CELL 4  
CELL 2  
CELL 3  
Sector  
X
Sector  
Y
Sector  
Y
Sector  
Y
Sector  
Z
CELL 3  
Sector  
Y
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2-4 Cell Site Configurations  
60° sectorized configuration  
In a 60° (N=4) sectorized configuration, the 416 RF channels are divided  
among a group of four cells. Each cell contains a maximum of 104 RF  
channels, with six Control channels for each cell. Since each cell is further  
divided into six sectors, each sector will contain a maximum of 16 or 17 RF  
channels, with one Control channels for each sector. The RF channels are  
reused by other groups of cells.  
Figure 2-3 shows the layout of a 60° (N=4) sectorized frequency reuse plan.  
The RF channels used in Cell 1 of a cluster are reused in Cell 1 of other  
clusters, channels in Cell 2 are reused in Cell 2 of other clusters and so on.  
This arrangement will have the RF channels on the same carrier frequency in  
different areas to be separated from one another by the greatest possible  
distance so that co-channel interference is minimized.  
However, 60° sectorization is difficult to expand and optimize due to a more  
demanding environment of frequency re-use.  
Figure 2-3  
60° (N=4) sectorized frequency reuse plan  
Sector  
X
Sector  
Y
Sector  
W
CELL 2  
Sector  
X
Sector  
X
Sector  
V
Sector  
Z
Sector  
U
Sector  
W
Sector  
Y
Sector  
Y
Sector  
W
CELL 1  
CELL 3  
Sector  
X
Sector  
X
Sector  
V
Sector  
X
Sector  
V
Sector  
Z
Sector  
Z
Sector  
W
Sector  
Y
Sector  
U
Sector  
Y
CELL 4  
Sector  
W
Sector  
Y
Sector  
W
Sector  
U
CELL 2  
CELL 2  
Sector  
V
Sector  
X
Sector  
X
Sector  
X
Sector  
Z
Sector  
V
Sector  
X
Sector  
V
Sector  
Z
Sector  
Z
Sector  
W
Sector  
U
Sector  
W
Sector  
U
Sector  
W
Sector  
Y
Sector  
Y
Sector  
Y
Sector  
Y
Sector  
U
Sector  
W
CELL 3  
CELL 1  
CELL 1  
CELL 3  
Sector  
V
Sector  
X
Sector  
X
Sector  
Sector  
X
Sector  
V
Sector  
V
Sector  
Z
Sector  
Z
Sector  
V
Sector  
Z
Z
Sector  
W
Sector  
U
Sector  
W
Sector  
Y
Sector  
U
Sector  
U
Sector  
W
Sector  
Y
Sector  
U
Sector  
Y
CELL 4  
CELL 4  
CELL 2  
Sector  
V
Sector  
X
Sector  
X
Sector  
V
Sector  
V
Sector  
Z
Sector  
Z
Sector  
Z
Sector  
U
Sector  
W
Sector  
U
Sector  
U
Sector  
W
Sector  
Y
Sector  
Y
CELL 1  
CELL 3  
Sector  
X
Sector  
V
Sector  
V
Sector  
Z
Sector  
Z
Sector  
U
Sector  
W
Sector  
Y
Sector  
U
CELL 4  
Sector  
V
Sector  
Z
Sector  
U
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3-1  
3
Cell Site Layouts  
This chapter provides information on the layout and cabling of the different  
DualMode Metrocell configurations.  
Important  
For ALL Metrocell cell site configurations, the frequency  
plan used should have a minimum of 21 channel spacing  
(630 kHz) between the channels in one RF Frame.  
Note: The DualMode Metrocell supports only Transmit Receive Units  
(TRU) with Product Engineering Code (PEC) NTAX98AA. No other  
radios can be used. The NTAX98AA TRU supports full digital and analog  
transmissions in accordance with IS-54 and IS-41 standards.  
Omni cell site configuration  
The Metrocell in an omni configuration uses at least two equipment frames,  
one CE Frame and one RF frame (see Figure 3-1). With only one RF frame,  
the maximum number of Voice Channels (VCH) supported by the cell site is  
22 since two of the 24 TRUs have to be assigned as the Control Channel  
(CCH) and the Locate Channel Receiver (LCR). As traffic grows, four  
additional RF frames can be added to the site to accommodate up to a  
maximum of 120 channels, including the CCH and the LCR.  
An RF Frame with up to 20 channels requires only one duplexer in the RF  
Frame and one TX/RX antenna. The outputs of the three AutoTune  
Combiners (ATC) are combined through one phasing transformer (located at  
ATC 2) and then connected to Duplexer position 2. This configuration  
requires a RX only antenna for the diversity receive function of the cell. See  
Figure 3-2.  
An RF Frame with 21 channels or more requires two duplexers in the RF  
Frame and two TX/RX antennas. The outputs of the lower and middle ATCs  
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3-2 Cell Site Layouts  
(ATC 1 and ATC 2) are combined through one phasing transformer (located at  
ATC 2) and then connected to Duplexer position 2 and the main TX/RX  
Antenna. The output of the upper ATC (ATC 3) is connected to Duplexer  
position 3 and the diversity TX/RX Antenna. This arrangement is used to  
meet the requirement of a minimum of 21 channel spacing (630 kHz)  
between the channels in one RF Frame. This configuration requires a TX/RX  
antenna to perform the diversity receive function of the cell. See Figure 3-3.  
Control Channel redundancy  
Control Channel (CCH) redundancy is commonly provided with a Locate  
Channel Receiver (LCR) backup. The CCH is assigned to position 1 on the  
TRU/DPA Shelf 1 and the LCR is assigned to position 4 on the same shelf.  
This arrangement will have the CCH and the LCR supplied on a different DC  
power feed and a TCM card. No RF coaxial switch is required since the  
cavity of the LCR position on the ATC will tune to the CCH frequency when  
backup is required.  
Figure 3-1  
Frame layout of an omni Metrocell with one RF frame (front view)  
CE Frame  
RF Frame 1  
RF RIP  
Duplexer Duplexer Duplexer  
CE RIP  
DRUM  
Position 3 Position 2 Position 1  
ACU  
ATC 3  
HSMO  
DPA DPA  
11 12  
CSM2  
TRU/DPA  
Shelf 3  
RMC 1  
DPA DPA  
9
10  
ATC 2  
Blank Panel  
ICRM  
DPA DPA  
7
8
TRU/DPA  
Shelf 2  
DPA DPA  
5
6
ATC 1  
DPA DPA  
3
4
TRU/DPA  
Shelf 1  
Blank Panel  
Base  
DPA DPA  
1
2
Base  
Note: For a frame with up to 20 channels, only one duplexer (located in  
position 2) is required.  
For a frame with 21 channels or more, two duplexers (located in  
positions 2 and 3) are required.  
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Cell Site Layouts 3-3  
Figure 3-2  
Block diagram of an omni Metrocell with up to 20 channels in one RF Frame  
RF Frame 1  
(Note 1)  
See Table 3-3 for  
RMC/TRU Shelf connection  
Antenna  
(Main  
receive)  
A1  
A2  
A3  
TX  
Control Channel  
(Note 2)  
Duplexer  
Position 2  
RX  
ANT  
A8  
DPA 1  
Antenna  
(Diversity  
receive)  
B1  
B2  
B3  
TRU/DPA  
Shelf 1  
ATC 1  
B8  
DPA 4  
See Table 3-1 for  
PA/ATC connection  
DPA 5  
Notes:  
ATC 2  
TRU/DPA  
1. For diagram clarity, only one RF Frame is  
shown. Other RF Frames with 20 channels  
or less are connected and operated  
Shelf 2  
identically to that of RF Frame 1.  
2. TRU1 at TRU/DPA Shelf 1 of RF Frame 1 is  
assigned as the CCH and TRU4 at the same  
shelf is assigned as the backup CCH.  
DPA 8  
DPA 9  
TRU/DPA  
Shelf 3  
ATC 3  
DPA 10  
CE Frame  
ICRM  
HSMO  
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3-4 Cell Site Layouts  
Figure 3-3  
Block diagram of an omni Metrocell with 21 to 24 channels in one RF Frame  
See Table 3-3 for  
RMC/TRU Shelf connection  
RF Frame 1  
(Note 1)  
Antenna  
(Main  
receive)  
A1  
A2  
A3  
TX  
Control Channel  
(Note 2)  
Duplexer  
Position 2  
RX  
ANT  
A8  
DPA 1  
Antenna  
(Diversity  
receive)  
B1  
B2  
B3  
TX  
RX Duplexer ANT  
TRU/DPA  
Shelf 1  
Position 3  
ATC 1  
B8  
DPA 4  
DPA 5  
See Table 3-2 for  
PA/ATC connection  
Notes:  
ATC 2  
TRU/DPA  
1. For diagram clarity, only one RF Frame is  
shown. Other RF Frames with 21 channels  
or mor are connected and operated  
Shelf 2  
identically to that of RF Frame 1.  
2. TRU1 at TRU/DPA Shelf 1 of RF Frame 1 is  
assigned as the CCH and TRU4 at the same  
shelf is assigned as the backup CCH.  
DPA 8  
DPA 9  
TRU/DPA  
Shelf 3  
ATC 3  
DPA 12  
CE Frame  
ICRM  
HSMO  
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Cell Site Layouts 3-5  
Transmit cabling  
In the transmit path, the output of each Transmit Receive Unit (TRU) is  
connected to the input of each corresponding power amplifier (PA) on the  
Dual Power Amplifier (DPA) module. The output of each power amplifier  
(PA) is input to an 8-channel AutoTune Combiner (ATC).  
The output of the ATC is connected to the Transmit (TX) port of the duplexer.  
For RF Frames using more than one ATC, the outputs of the ATCs are  
combined together and connected to the TX port of the duplexer. The  
duplexer serves as the interface between the antenna system and the RF  
frame. Table 3-1 lists the connection between the PAs and the ATC for an RF  
Frame with up to 20 channels. Table 3-2 lists the connection between the PAs  
and the ATC for an RF Frame with 21 channels or more.  
Table 3-1  
RF Frame 1 PA to ATC connection for an omni Metrocell with up to 20 channels  
From  
Through  
ATC1 - Port 1  
To  
DPA 1 - Port1 (CCH)  
DPA 1 - Port2  
DPA 2 - Port1  
DPA 2 - Port2 (LCH)  
DPA 3 - Port1  
DPA 3 - Port2  
DPA 4 - Port1  
DPA 4 - Port2  
DPA 5 - Port1  
DPA 5 - Port2  
DPA 6 - Port1  
DPA 6 - Port2  
DPA 7 - Port1  
DPA 7 - Port 2  
DPA 8 - Port1  
DPA 8 - Port 2  
DPA 9 - Port1  
DPA 9 - Port 2  
DPA 10 - Port1  
DPA 10 - Port2  
ATC1 - Port 2  
ATC1 - Port 3  
ATC1 - Port 4  
ATC1 - Port 5  
ATC1 - Port 6  
ATC1 - Port 7  
ATC1 - Port 8  
ATC2 - Port 1  
ATC2 - Port 2 Duplexer  
TRU/DPA  
Shelf 1  
ATC Shelf 1  
Antenna  
(Main receive)  
Position 2  
ATC2 - Port 3  
TRU/DPA  
Shelf 2  
ATC Shelf 2  
ATC2 - Port 4  
ATC2 - Port 5  
ATC2 - Port 6  
ATC2 - Port 7  
ATC2 - Port 8  
ATC3 - Port 1  
ATC3 - Port 2  
ATC3 - Port 3  
ATC3 - Port 4  
TRU/DPA  
Shelf 3  
ATC Shelf 3  
Note: Additional RF Frames with 20 channels or less are connected to  
their respective TX/RX antennas in the same way as RF Frame 1.  
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3-6 Cell Site Layouts  
Table 3-2  
RF Frame 1 PA to ATC connection for an omni Metrocell with 21 channels or more  
From  
Through  
ATC1 - Port 1  
To  
DPA 1 - Port1 (CCH)  
DPA 1 - Port2  
DPA 2 - Port1  
DPA 2 - Port2 (LCH)  
DPA 3 - Port1  
DPA 3 - Port2  
DPA 4 - Port1  
DPA 4 - Port2  
DPA 5 - Port1  
DPA 5 - Port2  
DPA 6 - Port1  
DPA 6 - Port2  
DPA 7 - Port1  
DPA 7 - Port 2  
DPA 8 - Port1  
DPA 8 - Port 2  
DPA 9 - Port1  
DPA 9 - Port 2  
DPA 10 - Port1  
DPA 10 - Port2  
DPA 11 - Port1  
DPA 11 - Port 2  
DPA 12 - Port1  
DPA 12 - Port2  
ATC1 - Port 2  
ATC1 - Port 3  
TRU/DPA  
Shelf 1  
ATC Shelf 1  
ATC Shelf 2  
ATC Shelf 3  
ATC1 - Port 4  
ATC1 - Port 5  
ATC1 - Port 6  
ATC1 - Port 7  
ATC1 - Port 8 Duplexer  
Antenna  
(Main receive)  
Position 2  
ATC2 - Port 1  
ATC2 - Port 2  
ATC2 - Port 3  
ATC2 - Port 4  
ATC2 - Port 5  
ATC2 - Port 6  
ATC2 - Port 7  
ATC2 - Port 8  
ATC3 - Port 1  
ATC3 - Port 2  
ATC3 - Port 3  
ATC3 - Port 4 Duplexer  
TRU/DPA  
Shelf 2  
TRU/DPA  
Shelf 3  
Antenna  
(Diversity  
receive)  
Position 3  
ATC3 - Port 5  
ATC3 - Port 6  
ATC3 - Port 7  
ATC3 - Port 8  
Note: Additional RF Frames with 21 channels or more are connected to  
their respective TX/RX antennas in the same way as RF Frame 1.  
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Cell Site Layouts 3-7  
Receive cabling  
In the reverse path, the receive signal from the main antenna is connected to  
the A-input of the Receive Multicoupler (RMC) through the receive port of  
the duplexer. The diversity antenna connects directly to the B-input of the  
RMC. Distribution of the reverse path frequencies is accomplished by RF  
splitters within each RF frame.  
Table 3-3 shows the connection between the RMC and the splitters.  
Table 3-3  
RMC to splitter connections for an Omni Metrocell  
From  
Through  
To  
Splitter 1  
Main antenna  
RMC 1A - A1  
RMC 1B - B1  
RMC 1A - A2  
RMC 1B - B2  
RMC 1A - A3  
RMC 1B - B3  
TRU Shelf 1  
TRU Shelf 1  
TRU Shelf 2  
TRU Shelf 2  
TRU Shelf 3  
TRU Shelf 3  
Diversity antenna  
Main antenna  
Splitter 4  
Splitter 1  
Splitter 4  
Splitter 1  
Splitter 4  
Diversity antenna  
Main antenna  
Diversity antenna  
Component requirement  
Table 3-4 lists the components required for a Metrocell with one to five RF  
Frames. An omni cell site requires only one Receive Multicoupler (RMC).  
Table 3-4  
Component requirement for an omni Metrocell  
No. of RF  
Frames  
No. of  
TRUs  
No. of  
ATCs  
Duplexer  
per frame  
ICRM TCM  
Port cards  
No. of  
antennas  
Configuration  
with up to 20  
channels per  
RF Frame  
1
2
3
4
5
1
2
3
4
5
3 to 20  
21 to 40  
41 to 60  
61 to 80  
81 to 100  
3 to 24  
1 to 3  
4 to 6  
1
1
1
1
1
2
2
2
2
2
2
4
6
6
8
2
4
6
6
8
1 TX/RX, 1 RX  
2 TX/RX  
7 to 9  
2 TX/RX, 1 TX  
2 TX/RX, 2 TX  
2 TX/RX, 3 TX  
2 TX/RX  
10 to 12  
13 to 15  
1 to 3  
Configuration  
with up to 24  
channels per  
RF Frame  
25 to 48  
49 to 72  
73 to 96  
97 to 120  
4 to 6  
2 TX/RX, 2 TX  
2 TX/RX, 4 TX  
2 TX/RX, 6 TX  
2 TX/RX, 8 TX  
7 to 9  
10 to 12  
13 to 15  
Note: An additional TCM port card is required for the DRUM, the ACU  
and the CSM2.  
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3-8 Cell Site Layouts  
120° STSR cell site configuration  
The Metrocell in a 120° STSR configuration uses at least two equipment  
frames, one CE Frame and one RF frame (see Figure 3-4). Each TRU/DPA  
Shelf and its associated ATC on the RF frame support one of the three sectors.  
With only one RF frame, the maximum number of Voice Channels (VCH)  
supported by each sector is six since two of the eight TRUs on the TRU shelf  
have to be assigned as the Control Channel (CCH) and the Locate Channel  
Receiver (LCR). A 120° STSR Metrocell with one RF Frame requires six  
antennas; one TX/RX antenna and one RX only antenna for each sector (see  
Figure 3-6). As traffic grows, two additional RF frames can be added to  
accommodate more VCHs (see Figure 3-5).  
A 120° STSR Metrocell with three RF Frames requires six antennas. It may  
be three TX/RX antennas and three RX only antennas or six TX/RX antennas  
depending on the number of channels in each RF Frame. An RF Frame with  
20 channels or less in one sector requires one duplexer in the RF Frame and  
one TX/RX antennas for that sector. The outputs of the three combiners are  
combined through one phasing transformer (located at ATC 2) and connected  
to Duplexer position 2 in that RF Frame. The output of the duplexer is then  
connected to the main TX/RX Antenna of that sector).  
An RF Frame with 21 channels or more in one sector requires two duplexers  
in the RF Frame and two TX/RX antennas for that sector. The outputs of ATC  
1 and ATC 2 are combined through one phasing transformer (located at ATC  
2) and connected to Duplexer position 2 in that RF Frame. The output of the  
duplexer is then connected to main TX/RX Antenna of that sector. The output  
of ATC 3 is connected to Duplexer position 3 and then to the diversity TX/RX  
Antenna of that sector. This arrangement is used to meet the requirement of a  
minimum of 21 channel spacing (630 kHz) between the channels in one RF  
Frame. Figure 3-5 shows the frame layout and Figure 3-7 shows the block  
diagram of a 120° STSR Metrocell with three RF Frames.  
Control Channel redundancy  
Control Channel (CCH) redundancy is commonly provided with a Locate  
Channel Receiver (LCR) backup. With one RF Frame, the CCH of each  
sector is assigned to position 1 on the TRU/DPA Shelf of that sector and the  
LCR is assigned to position 4 on the same shelf. With three RF Frames, the  
CCH of each sector is assigned to position 1 on TRU/DPA Shelf 1 of that  
sector and the LCR is assigned to position 4 on the same shelf. This  
arrangement will have the CCH and the LCR supplied on a different DC  
power feed and a TCM card. No RF coaxial switch is required since the  
cavity of the LCR position on the ATC will tune to the CCH frequency when  
backup is required.  
411-2021-111 Standard 01.01 June 1996  
Download from Www.Somanuals.com. All Manuals Search And Download.  
Cell Site Layouts 3-9  
Figure 3-4  
Frame layout of a 120° STSR Metrocell site with one RF frame (front view)  
CE Frame  
RF Frame 1  
RF RIP  
CE RIP  
Duplexer Duplexer Duplexer  
Position 3 Position 2 Position 1  
(Sector Z) (Sector Y) (Sector X)  
DRUM  
ATC 3  
(Sector Z)  
ACU  
HSMO  
DPA DPA  
TRU/DPA  
Shelf 3  
(Sector Z)  
CSM 2  
11  
12  
RMC 1 (Sector X)  
RMC 2 (Sector Y)  
RMC 3 (Sector Z)  
DPA DPA  
10  
9
ATC 2  
(Sector Y)  
Blank Panel  
DPA DPA  
TRU/DPA  
Shelf 2  
(Sector Y)  
7
8
DPA DPA  
5
6
ICRM  
ATC 1  
(Sector X)  
DPA DPA  
TRU/DPA  
Shelf 1  
(Sector X)  
3
4
Blank Panel  
Base  
DPA DPA  
1
2
Base  
Figure 3-5  
Frame layout of a 120° STSR Metrocell site with three RF frames (front view)  
RF Frame 1  
(Sector X)  
RF Frame 2  
(Sector Y)  
RF Frame 3  
(Sector Z)  
CE Frame  
RF RIP  
RF RIP  
RF RIP  
CE RIP  
Duplexer Duplexer Duplexer  
Duplexer Duplexer Duplexer  
Duplexer Duplexer Duplexe  
DRUM  
Position 3 Position 2 Position 1  
Position 3 Position 2 Position 1  
Position 3 Position 2 Position 1  
ACU  
ATC 3  
ATC 3  
ATC 3  
HSMO  
DPA DPA  
DPA DPA  
11 12  
DPA DPA  
CSM 2