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TRACER 4102/4202 System Manual

Section 2  Microwave Path Engineering Basics

612804202L1-1A

© 2004 ADTRAN, Inc.

15

1.

LINE-OF-SIGHT

The TRACER 4102 and 4202 systems are designed for operation in the license-free 2.400 to 2.4835 GHz 
and 5.725 GHz to 5.850 GHz industrial, scientific and medical (ISM) bands, respectively. Radio wave 
propagation in these bands exhibit microwave characteristics which are ideally suited for point-to-point, 
line-of-sight communications. Line-of-Sight requires that the transmitting antenna and receiving antenna 
are able to “see” each other, and that the straight-line path between the two antennas is free of obstructions, 
such as buildings, trees, mountains, and, in longer paths, even the curvature of the earth. In addition, for 
maximum signal strength the area around the visual line-of-sight where microwave signals reflect (Fresnel 
zone) must also be free of obstructions. Fresnel zones are discussed in more detail on page 22.

Terminology

2.

DECIBELS

Understanding the decibel (dB) format is key when discussing microwave path engineering because the 
received signal power is often expressed in decibel format. In general, any quantity can be expressed in 
decibels. If the quantity 

x

 is a power level (in Watts), the decibel equivalent is defined as

If the quantity 

x

 is referenced to a milliwatt (mW), then the decibel-milliwatt (dBm) is used instead of a 

generic decibel.

Using the decibel format simplifies power calculations by reducing multiplication and division operations 
into addition and subtraction operations.

3.

CALCULATING THE FADE MARGIN

The fade margin (

) is a value in decibels (dB) that represents the amount of signal reduction that can be 

tolerated before the link exceeds the specified bit error rate (BER). Fade margin is simply the difference 
between the available signal power at the receiver (

P

) and the receiver sensitivity (

P

sens

 ). 

Higher levels of fade margin indicate stronger protection against signal fading and a more reliable link. For 

Point-to-Point

Wireless communication from a single site to another individual 
site. Contrast with point-to-multipoint.

Line-of-Sight

An unobstructed, direct path exists between the transmitting and 
the receiving antennas.

It is imperative to determine if the proposed microwave path is suitable (at a minimum) for 
ideal, nondistorted signals before attempting installation.

x

dB

10 log

10

x

( )

=

(dB)

x

dBm

10 log

10

x

1mW

-------------

=

(dBm)

F

P

R

P

sens

=

(dB)

= P

T

 + G

T

 + G

R

 - L - L

P

 - 

P

sens

Summary of Contents for 12804102L1A

Page 1: ...4202L1 1A January 2004 TRACER 4102 4202 System Manual 12804102L1A TRACER 4102 System Plan A 12804102L1B TRACER 4102 System Plan B 12804202L1A TRACER 4202 System Plan A 12804202L1B TRACER 4202 System P...

Page 2: ...ntial damages or for commercial losses even if ADTRAN has been advised thereof as a result of issue of this publication About this Manual This manual provides a complete description of the TRACER 4102...

Page 3: ...cument Revision Date Description of Changes A January 2004 Initial release of manual Notes provide additional useful information Cautions signify information that could prevent service interruption Wa...

Page 4: ...bowl kitchen sink laundry tub in a wet basement or near a swimming pool 2 Avoid using a telephone other than a cordless type during an electrical storm There is a remote risk of shock from lightning 3...

Page 5: ...can radiate radio frequency energy If not installed and used in accordance with the instructions it may cause interference to radio communications The limits are designed to provide reasonable protec...

Page 6: ...quipment The installed antenna must not be located in a manner that allows exposure of the general population to the direct beam path of the antenna at a distance less than 15 feet 4 6 meters Installa...

Page 7: ...se contact our Customer and Product Service CaPS department to have an RMA number issued CaPS should also be contacted to obtain information regarding equipment currently in house or possible fees ass...

Page 8: ...tended Services ACES program offers multiple types and levels of installation and maintenance services which allow you to choose the kind of assistance you need This support is available at For questi...

Page 9: ...re defined and several recommendations are offered Section 3 Engineering Guidelines 25 Provides information to assist network designers with incorporating the TRACER 4102 4202 system into their networ...

Page 10: ...Table of Contents TRACER 4102 4202 System Manual 10 2004 ADTRAN Inc 612804202L1 1A...

Page 11: ...ation about the TRACER 4102 4202 It contains general information and describes physical and operational concepts network relationships provisioning testing alarm status and system monitoring This sect...

Page 12: ...through a separate maintenance channel The TRACER 4102 4202 has several built in test capabilities including remote loopback Complete configuration and performance data is available through menus acc...

Page 13: ...sses L 18 Path Loss LP 19 Receiver Sensitivity 20 Antenna Information 21 Antenna Alignment 21 TRACER RSSI Test Points 21 Antenna Beam Patterns 21 Fresnel Zones Earth Curvature Antenna Heights 22 Other...

Page 14: ...Section 2 Microwave Path Engineering Basics TRACER 4102 4202 System Manual 14 2004 ADTRAN Inc 612804202L1 1A...

Page 15: ...d in decibel format In general any quantity can be expressed in decibels If the quantity x is a power level in Watts the decibel equivalent is defined as If the quantity x is referenced to a milliwatt...

Page 16: ...ed signal power to the other microwave parameters is or in decibel notation where the variables in the equations are defined as PR received power dBm PT transmitted power adjustable up to 20 dBm maxim...

Page 17: ...however dish manufacturers can provide gains for specific types of antennas Transmitted Power PT The FCC specifies the maximum transmitter power that may be used for antennae of a given gain FCC Rule...

Page 18: ...for the power budget analysis Coaxial cable is required to attach the TRACER 4102 4202 to the antenna The length of the cable varies from a few feet to hundreds of feet depending upon your applicatio...

Page 19: ...is expressed in miles and f in GHz Path loss as shown here increases rapidly as either the path length increases or the carrier wavelength decreases which happens as the carrier frequency increases Th...

Page 20: ...ver electronics Receiver sensitivity of the TRACER 4102 4202 is dynamic as a function of desired bandwidth receiver sensitivity improves as delivered bandwidth decreases In situations where 2xT1 conne...

Page 21: ...4202 can be viewed from the local TRACER 4102 4202 VT100 terminal menu interface An RSSI test point provides a DC voltage level relative to the GND test point that corresponds to the amount of signal...

Page 22: ...d Fresnel zones 2 4 6 add destructively at the receiver The first Fresnel zone corresponds to the main lobe 60 of which must be free of physical obstructions for the path calculations to be valid Sinc...

Page 23: ...y microwave signals will be randomly dispersed over rough terrain and will not interfere with the main signal lobe as badly as in the smooth terrain case The terrain factor values normally used are li...

Page 24: ...s TRACER 4102 4202 System Manual 24 2004 ADTRAN Inc 612804202L1 1A values normally used are listed below Climate Climate Factor Description Very Dry 1 8 desert regions Temperate 1 4 mainland interior...

Page 25: ...C Power Connection Plug In Terminal Block 31 Fuse 31 Antenna Interface N Type connector 32 At A Glance Specifications 32 FIGURES Figure 1 TRACER 4202 Front Panel Layout 26 Figure 2 TRACER 4102 4202 Re...

Page 26: ...ing Interface The RSSI voltage is a function of the signal strength at the receiver and is used to measure the received signal strength RSSI varies from approximately 0 to 5 Volts DC VDC An RSSI Calib...

Page 27: ...quency Plan A Off the TRACER 4102 4202 is not transmitting on Frequency Plan A PLAN B Green solid the TRACER 4102 4202 is transmitting on Frequency Plan B Off the TRACER 4102 4202 is not transmitting...

Page 28: ...ions including pinouts of rear panel components where applicable follow the table Name Connector Description A RS 232 DB 25 female VT100 terminal or PC with terminal emulation software connection B Te...

Page 29: ...CER 4102 4202 must be interfaced to a modem via an RS 232 null modem adapter or cable The null modem converts Clear To Send CTS and Data Set Ready DSR into Ready To Send RTS and Data Terminal Ready DT...

Page 30: ...tandards Hangup on DTR drop may need to be explicitly enabled on some modems The null modem interface must route Carrier Detect CD on pin 8 directly from the modem When using the RS 232 interface for...

Page 31: ...oltage in Volts For example at 48 V TRACER 4102 4202 would draw approximately 0 417 A 20 W 48 V The terminal of the DC power connection must be connected to the most positive voltage rail while the te...

Page 32: ...cification Transmitter Output Power 20 dBm max Frequency Range 2400 to 2483 5 MHz TRACER 4102 5725 to 5850 MHz TRACER 4202 Receiver Receive Level Minimum TRACER 4102 96 dBm 2xT1 98 dBm 1xT1 TRACER 420...

Page 33: ...nu Driven User Interface Control of the Remote End Loopback Test Optional Password Protection Event History VT100 Terminal Interface Data Rate 9600 bps Data Bits 8 Parity None Stop Bits 1 Terminal Emu...

Page 34: ...Section 3 Engineering Guidelines TRACER 4102 4202 System Manual 34 2004 ADTRAN Inc 612804202L1 1A...

Page 35: ...d 36 Unpack and Inspect the System 36 Contents of ADTRAN Shipment 36 Customer Provides 37 Channel Selection 37 Grounding Instructions 38 Supplying Power to the Unit 39 Mounting Options 39 Connecting t...

Page 36: ...p objects After unpacking the unit inspect it for possible shipping damage If the equipment has been damaged in transit immediately file a claim with the carrier then contact ADTRAN Customer Service s...

Page 37: ...antenna installation 4 CHANNEL SELECTION The FCC has allocated 83 5 MHz of spectrum in the 2 4 GHz band where the TRACER 4102 operates and 125 MHz of spectrum in the 5 8 GHz band where the TRACER 420...

Page 38: ...idually covered or insulated equipment grounding conductors shall have a continuous outer finish that is either green or green with one or more yellow stripes The equipment grounding conductor is to b...

Page 39: ...ed rackmount brackets 3265498 B Follow these steps to mount the TRACER 4102 4202 into a rack This unit shall be installed in accordance with Article 400 and 364 8 of the NEC NFPA 70 when installed out...

Page 40: ...4 23 inch Rackmount Illustration 8 CONNECTING THE T1 INTERFACE The physical T1 interface is provided using two RJ 48C jacks for transmit and receive The provided straight through T1 interface cables...

Page 41: ...criptions 44 TRACER System Status 44 Main Menu 46 TRACER System Options 47 TRACER Link Performance History 50 T1x Status Configuration Loopback 51 T1x Performance History 54 FIGURES Figure 1 Main Menu...

Page 42: ...nce a terminal is connected press Ctrl L to refresh the current screen If password access has been enabled the ENTER PASSWORD message displays at the bottom of the TRACER 4102 4202 System Status menu...

Page 43: ...ivity on the terminal The password is enabled and defined via the system options menu To do this Press this key Move up to select items Up Arrow P Prev Move down to select items Down Arrow N Next Edit...

Page 44: ...upport toll free contact number is located directly beneath the elapsed time display at the top of the TRACER 4102 4202 System Status menu page C RF Status A graphical indicator of the TRACER RF link...

Page 45: ...202 unit For an operational TRACER 4102 4202 system you should have a frequency plan A radio at one end of the link and a frequency plan B radio at the other end of the link I Rx Quality Displays an i...

Page 46: ...us pages Figure 3 shows the TRACER 4102 4202 Main Menu page Figure 3 TRACER 4102 4202 Main Menu From the keyboard use the up and down arrow keys to scroll through the available pages or enter the numb...

Page 47: ...symbols This parameter is display only TRACER SYSTEM OPTIONS TX POWER Allows the transmitter levels for both the local and remote units to be adjusted The current transmitter level is displayed using...

Page 48: ...ision respectively The TRACER 4102 4202 comes factory programmed with RF bandplan set to Band 1 Figure 5 2 4 GHz Bandwidth Division TRACER 4102 Figure 6 5 8 GHz Bandwidth Division TRACER 4202 TRACER S...

Page 49: ...current session and return to the TRACER System Status menu page and wait for password input TRACER SYSTEM OPTIONS PASSWORD ENABLE Configures password protection for the VT100 terminal interface Pass...

Page 50: ...ss the wireless link and are generally an indication of path or interference problems The link error count and minimum received signal level for the most recent 24 hours are recorded in 15 minute incr...

Page 51: ...S Yellow LOS and bipolar violations BPV Table 2 briefly describes these alarms See Section 6 Troubleshooting Guide for more information on these alarms The following menus for the T1x Status Configura...

Page 52: ...R 4102 4202 to monitor incoming framing error events and indicate problems with the attached metallic service The TRACER 4102 4202 supports both extended superframe ESF and superframe D4 framing forma...

Page 53: ...k Loopback T1X STATUS CONFIGURATION LOOPBACK LOOP NORMAL STATE LINE LOCAL Activates a loopback at the local TRACER 4102 4202 T1 framer towards the locally connected T1 equipment see Figure 11 Use the...

Page 54: ...events qualify as an ES AIS LOS or LOF Alarm Second a single bipolar violation BPV excessive zero event or a single parity bit An SES is caused by an AIS LOS or LOF Alarm Second excessive BPVs or fram...

Page 55: ...common configuration problems for the TRACER 4102 4202 CONTENTS Overview 56 LED Indicators 56 PWR LED 56 TST LED 56 RF DOWN LED 56 RF LOW LED 57 T1 Interface Alarm LEDs 57 RF Errors 58 Step by Step Tr...

Page 56: ...n progress If the TST LED is blinking or remains ON after 10 seconds this indicates that the TRACER 4102 4202 unit has failed the self test This is an internal failure and ADTRAN technical support sho...

Page 57: ...Recommended Actions 1 Display the T1 X STATUS screen and check the T1 X INTERFACE ALARM field to identify the active alarm 2 Follow the steps below for the appropriate alarm LOS Alarm Red Alarm LOS AL...

Page 58: ...at the actual receive signal level agrees with the calculated receive signal An RSSI test point located on the front panel provides a DC voltage level relative to the GND test point that corresponds t...

Page 59: ...eeding 8 Attach the RF coaxial cables to a high quality attenuator if possible If you do not have an attenuator attach the coaxial cables to the antennas to be used in the permanent installation If th...

Page 60: ...nk loopback on the remote TRACER 4102 4202 unit and run a test pattern from the connected T1 equipment This will verify the data path across the RF link Installing Configuring T1 Hardware 1 If possibl...

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