12806410L2ATRACER 6410 2.4 GHz (High Power) System (Plan A)
12806410L2BTRACER 6410 2.4 GHz (High Power) System (Plan B)
12806420L1ATRACER 6420 5.8 GHz System (Plan A)
12806420L1BTRACER 6420 5.8 GHz System (Plan B)
612806420L1-1D
September 2005
TrademarksTRACER 6000 Series Integrated System Manual
Trademarks
Any brand names and product names included in this manual are trademarks, registered trademarks, or
trade names of their respective holders.
To the Holder of the Manual
The contents of this manual are current as of th e date of publication. ADTRAN reserves the right to change
the contents without prior notice.
In no event will ADTRAN be liable for any special, incidental, or consequential 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 64x0 systems (TRACER 6410 and 6420)
and system software. The purpose of this manual is to provide the technician, system administrator, and
manager with general and specific information related to the planning, installation, operation, and
maintenance of the TRACER 64x0 systems. This manual is arranged so that needed information can be
quickly and easily found.
Safety InstructionsTRACER 6000 Series Integrated System Manual
Safety Instructions
When using your telephone equipment, please follow these basic safety precautions to reduce the risk of
fire, electrical shock, or personal injury:
1. Do not use this product near water, such as a bathtub, wash 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. Do not use the telephone to report a gas leak in the vicinity of the leak.
4. Use only the power cord, power supply, and/or batteries indicated in the manual. Do not dispose of
batteries in a fire. They may explode. Check with local codes for special disposal instructions.
TRACER 6000 Series Integrated System Manual FCC-Required Information
FCC-Required Information
Federal Communications Commission Radio Frequency Interference Statement
This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant
to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful
interference when the equipment is operated in a commercial environment. This equipment generates,
uses, and can radiate radio frequency energy and, if not installed and used in accordance with the
instruction manual, may cause harmful interference to radio frequencies. Operation of this equipment in a
residential area is likely to cause harmful interference, in which case the user will be required to correct the
interference at his own expense.
Shielded cables must be used with this unit to ensure compliance with Class A FCC limits.
Changes or modifications to this unit not expressly appr oved by the party responsible
for compliance could void the user’s authority to operate the equipment.
Radio Frequency Interface Statement
This equipment has been tested and found to comply with the limits for an intentional radiator, p ursuant to
Part 15, Subpart C of the FCC Rules. This equipment generates, uses, and 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 protection against such interference in a residential situation.
However, there is no guarantee that interference will not occur in a particular installation. If this equipment
does cause interference to radio or television reception, which can be determined by turning the equipment
on and off, the user is encouraged to try to correct the interference by one or more of the following
measures:
•Reorient or relocate the receiving antenna of the affected radio or television.
•Increase the separation between the equipment and the affected receiver.
•Connect the equipment and the affected receiver to power outlets on separate circuits.
•Consult the dealer or an experienced radio/TV technician for help.
Changes or modifications not expressly approved by ADTRAN could void the user’s
authority to operate the equipment.
FCC-Required InformationTRACER 6000 Series Integrated System Manual
FCC Output Power Restrictions
The FCC does not require licensing to implement this device. License-free operation in the industrial,
scientific, and medical band is documented in FCC Rules Part 15.247. It is the responsibility of the
individuals designing and implementing the radio system to ensure compliance with any pertinent FCC
Rules and Regulations. This device must be professionally installed.
The FCC specifies the maximum transmitter power used for antennae of a given gain. FCC Rules Part 15,
Subpart 247 allow for a maximum power of 1 watt (30 dBm) into antennae of a gain less than or equal to 6
dBi. At 2.4 GHz (TRACER 6410), the 1-watt maximum transmitter power must be reduced by 1 dB for
every 3 dB of antenna gain over 6 dBi. This rule is shown in Table 5 on page 20. For the 5.8 GHz band
(TRACER 6420), the maximum output power is 1 watt (30 dBm) regardless of the gain of the attached
antenna. Since the TRACER 6420 maximum transmit power is 100 milliwatts, there is reduction in
transmitter output power required.
Exposure to Radio Frequency Fields
The TRACER 6410 is designed to operate at 2.4 GHz with 500 mW maximum transmit power, and the
TRACER 6420 is designed to operate at 5.8 GHz with 100 mW maximum transmit power.
This level of RF energy is below the Maximum Permissible Exposure (MPE) levels specified in FCC OET
65:97-01. The installation of high gain antenna equipment in the system configuration may create the
opportunity for exposure to levels higher than recommended for the general population at a distance less
than 15 feet (4.6 meters) from the center of the antenna. The following precautions must be taken during installation of this equipment:
Verify the antenna installation meets all regulations specified in the National Electric
Code (NEC) Article 810 with particular attention to clearances from power and lighting
conductors, mounting, grounding, and antenna discharge unit.
•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). Installation on towers,
masts, or rooftops not accessible to the general population is recommended; or
•Mount the antenna in a manner that prevents any personnel from entering the area within 15 feet
(4.6 meters) from the front of the antenna.
•It is recommended that the installer place radio frequency hazard warnings signs on the barrier that
prevents access to the antenna.
•Prior to installing the antenna to the TRACER output, make sure the power is adjusted to the settings
specified in Section 2 of this manual.
•During antenna installation, be sure that power to the TRACER equipment is turned off in order to
prevent the presence of microwave energy on the coaxial connector.
•During installation and alignment of the antenna, do not stand in front of the antenna assembly.
•During installation and alignment of the antenna, do not handle or touch the front of the antenna.
Per Industry Canada RSS210: “The installer of this radio equipment must ensure that the antenna is located
or pointed such that it does not emit RF field in excess of Health Canada limits for the general population;
consult Safety Code 6, obtainable from Health Canada’s website at www.hc-sc.gc.ca/rpb.These simple
precautions must be taken to prevent general population and installation personnel from exposure to RF
energy in excess of specified MPE levels.
TRACER 6000 Series Integrated System ManualWarranty and Customer Service Information
Warranty, Customer Service, Product Support Information, and T raining
ADTRAN will repair and return this product within the warranty period if it does not meet its published
specifications or fails while in service. Warranty information can be found at www.adtran.com/warranty.
A return material authorization (RMA) is required prior to returning equipment to ADTRAN. For service,
RMA requests, training, or more information, use the contact information given below.
Repair and Return
If you determine that a repair is needed, please 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 associated with repair.
CaPS Department(256) 963-8722
Identify the RMA number clearly on the package (below address), and return to the following address:
ADTRAN Customer and Product Service
901 Explorer Blvd. (East Tower)
Huntsville, Alabama 35806
RMA # _____________
Pre-Sales Inquiries and Applications Support
Your reseller should serve as the first point of contact for support. If additional pre-sales support is needed,
the ADTRAN Support website provides a variety of support services such as a searchable knowledge base,
latest product documentation, application briefs, case studies, and a link to submit a question to an
Applications Engineer. All of this, and more, is available at:
http://support.adtran.com
When needed, further pre-sales assistance is available by calling our Applications Engineering
Department.
Warranty and Customer Service InformationTRACER 6000 Series Integrated System Manual
Post-Sale Support
Your reseller should serve as the first point of contact for support. If additional support is needed, the
ADTRAN Support website provides a variety of support services such as a searchable knowledge base,
updated firmware releases, latest product documentation, service request ticket generation and
trouble-shooting tools. All of this, and more, is available at:
http://support.adtran.com
When needed, further post-sales assistance is available by calling our Technical Support Center. Please
have your unit serial number available when you call.
Technical Support(888) 4ADTRAN
Training
The Enterprise Network (EN) Technical Training Department offers training on our most popular
products. These courses include overviews on product features and functions while covering applications
of ADTRAN's product lines. ADTRAN provides a variety of training op tions, including customized
training and courses taught at our facilities or at your site. For more information about training, please
contact your Territory Manager or the Enterprise Training Coordinator.
Training Phone(800) 615-1176, ext. 7500
Training Fax(256) 963-6700
Training Emailtraining@adtran.com
This section of ADTRAN’s TRACER 6000 Series Integrated System Manual is designed for
use by network engineers, planners, and designers for overview information about the TRACER
64x0 systems.
This section of ADTRAN’s TRACER 6000 Series Integrated System Manual is designed for use by
network engineers, planners, and designers for overview information about the TRACER 64x0 systems.
It contains general information and describes physical and operational concepts, network relationships,
provisioning, testing, alarm status, and system monitoring. This section should be used in conjunction with
Section 3, Engineering Guidelines, of this manual.
Section 1 System DescriptionTRACER 6000 Series Integrated System Manual
1.SYSTEM OVERVIEW
The TRACER 64x0 provides license-free scalable connectivity for service providers and corporate
networks. These radios feature two modular network interface ports that can accommodate various
combinations of T1, E1, and Ethernet option cards up to 8xT1/E1 (16.384 Mbps). This flexibility provides
customized time division multiplexed (TDM) and packet solutions for voice and data applications in a
single platform. The TRACER 6410 and TRACER 6420 provide carrier class point-to-point connectivity
up to thirty miles in the 2.4 GHz and 5.8 GHz license-free Industrial, Scientific, and Medical (ISM) bands,
respectively.
Complete network management is supported via simple network management protocol (SNMP), Telnet
access, and a VT100 terminal interface (
T1/E1/Ethernet alarm conditions, enabling remote installations to report outages without requiring a truck
roll to diagnose problems. Version 2 standard management information bases (MIBs) are supported for all
interface cards, while an enterprise-specific MIB is provided for radio functionality. Triple-DES (3DES)
security provides additional protection from unauthorized access without requiring any additional external
security appliances. Encryption can also be disabled altogether. Future upgrades an d enh anc emen ts can be
added through FLASH firmware downloads via trivial file transfer protocol (TFTP) (on the Ethernet
interface) or XMODEM on the
CRAFT port.
Receive sensitivity is optimized through the use of extensive forward error correction and
high-performance receiver design techniques. Dynamic receive sensitivity allows the user to increase
receiver performance by decreasing the delivered bandwidth. This feature maximizes link performance by
customizing the delivered bandwidth to the specific needs of the installation. Three software selectable
channel plans are supported to simplify frequency coordination at co-located sites. Channel plans are
easily changed via any of the software management interfaces without the added expense of hardware
upgrades or spare filter assemblies.
CRAFT port). SNMP traps are implemented for all RF link and
TRACER 64x0 wireless solutions maximize equipment density through the combination of compact size
(only 1U rack space required), low power consumption, and high thermal transfer. TRACER 64x0 systems
can be deployed at twice the density of other available wireless products.
2.FEATURES AND BENEFITS
The following is a brief list of the TRACER 64x0 features and benefits:
Configuration and Management
•Easy-to-use VT100 control port (RS-232 interface) for configuration and monitoring
•End-to-end management bridging for forwarding management traffic across the RF link management
channel
•Remote configuration of both ends of the wireless link, from each end of the link
Operational
•No license required per FCC Rules Part 15.247
•Dual module slots for network connectivity
•Up to 8xT1 or E1 bandwidth (16.384 Mbps) using two 4xT1 or 4xE1 network modules
Section 2 Microwave Path Engineering BasicsTRACER 6000 Series Integrated System Manual
1.LINE-OF-SIGHT
The TRACER 6410 and TRACER 6420 systems are designed for operation in the license-free 2.400 to
2.483 GHz and 5.725 GHz to 5.850 GHz industrial, scientific, and medical (ISM) bands, respectively.
Radio wave propagation in these bands exhibits 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. 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 25.
Terminology
Point-to-PointWireless communication from a single site to another individual
site. Contrast with point-to-multipoint.
Line-of-SightAn unobstructed, direct path exists between the transmitting and
the receiving antennas.
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
x
dB
10 log10x()
⋅
=
(dB)
If the quantity x is referenced to a milliwatt (mW), then the decibel-milliwatt (dBm) is used instead of a
generic decibel.
x
dBm
=
10 log
⋅
⎛⎞
------------ -
10
⎝⎠
1mW
(dBm)
x
Using the decibel format simplifies power calculations by reducing multiplication and division operations
into addition and subtraction operations.
3.CALCULATING THE FADE MARGIN
It is imperative to determine whether the proposed micro w ave path is suitable (at a
minimum) for ideal, nondistorted signals before attempting instal lation.
The fade margin (F ) 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
TRACER 6000 Series Integrated System ManualSection 2 Microwave Path Engineering Basics
where the variables in the equations are defined as
P
P
P
G
G
R
sens
T
T
R
received power (dBm)
receiver sensitivity (dBm)
transmitted power (adjustable up to 20 dBm maximum)
transmit antenna gain (decibels referenced to an isotropic source – dBi)
receive antenna gain (dBi)
Lother losses (RF coaxial cable, etc. – dB)
L
P
path loss (dB)
Higher levels of fade margin indicate stronger protection against signal fading and a more reliable link . For
most applications, 20 to 30 dB of fade margin should ensure a reliable link.
The following sections further discuss the necessary power calculations and their components.
4.RECEIVER POWER
The viability of a particular microwave path is determined by the power of the transmitted microwave
signal, the transmit and receive antenna gain, distance, and accumulated system losses (such as RF coaxial
cable losses and path loss).
The equation relating received signal power to the other microwave parameters is
PTGTG
P
------------------------------=
R
π
()2d2L
4
2
λ
R
(watts, W)
or (in decibel notation)
= PT + GT + GR - L - L
P
R
where the variables in the equations are defined as
P
R
P
T
G
T
G
R
received power (dBm)
transmitted power (adjustable up to 20 dBm maximum)
transmit antenna gain (decibels referenced to an isotropic source – dBi)
receive antenna gain (dBi)
λcarrier wavelength (meters)
dpath distance (meters)
Lother losses (RF coaxial cable, etc. – dB)
L
P
path loss (dB)
When using decibel notation, all quantities must be individually converted to decibels
prior to performing addition and subtraction.
Section 2 Microwave Path Engineering BasicsTRACER 6000 Series Integrated System Manual
P
L
L
Figure 1 illustrates a wireless link configuration containing all the parameters necessary for the power
budget analysis.
λ
G
T
d, L
P
G
R
T
Figure 1. Example Microwave Path with Parameters
The following sections further discuss the power budget analysis and its components.
P
R
Antenna Gain
Actual transmit and receive antenna gain values depend strictly upon the physical characteristics of the
antennas installed for each link. In other words, the size of the dish determines the antenna gain. Using a
parabolic dish antenna results in the best performance. Antenna gains are specified in terms of decibels of
gain referenced to an isotropic source (dBi). An isotropic source is a hypothetical antenna having equal
radiation in all directions. The equation for calculating gain over isotropic radiation is
The carrier wavelength (λ) and dish diameter (D) can be metric or standard units of
measure. Use the same unit of measure for both variables. For example, a carrier
wavelength of 0.124 meters requires a dish diameter in me ters as well.
The dish efficiency factor (k) is used to estimate how efficiently the dish reflector passes energy to the
feedhorn. The “standard” factor is 0.55 (measured performance of prime-focus dishes with a pyrimidal
waveguide feedhorn with no aperture blockage). Other dishes and feedhorn designs may have better or
worse efficiency. Table 1 on page 19 (standard) an d Table 2 on page 19 (metric) provide gains using a 0.55
dish efficiency factor. Table 3 on page 19 (standard) and Table 4 on page 19 (metric) provide gains using a
0.40 dish efficiency factor. Dish manufacturers can provide gains for specific types of antennas.
Section 2 Microwave Path Engineering BasicsTRACER 6000 Series Integrated System Manual
Transmitted Power (PT)
The FCC specifies the maximum transmitter power used for antennae of a given gain. FCC Rules Part 15,
Subpart 247 allow for a maximum power of 1 watt (30 dBm) into antennae of a gain less than or equal to
6 dBi. At 2.4 GHz (TRACER 6410), the 1-watt maximum transmitter power must be reduced by 1 dB for
every 3 dB of antenna gain over 6 dBi. This rule is shown in Table 5 (for information only).
Table 5. Transmit Power Reduction for Various Antennae Gains
The TRACER 6410 is only approved to operate with dish antennas with a maximum gain of 21.1dBi.
For the 5.8 GHz band (TRACER 6420), the maximum output power is 1 watt (30 dBm) regardless of the gain
of the attached antenna. Since the TRACER 6420 maximum transmit power is 100 milliwatts, there is
Maximum
Antenna Gain
(dBi)
Maximum EIRP
(dBm)
reduction in transmitter output power required.
Carrier Wavelength (λ)
The carrier wavelength is the physical wavelength of the main RF carrier being used for communication, and
is usually approximated at the center frequency of the band (which is 2421.7 MHz for TRACER 6410 and
5787.5 MHz for the TRACER 6420). The carrier wavelength calculations follow.
λ = c / f (meters)
where
c = speed of light (in meters)
f = frequency (in Hz)
TRACER 6000 Series Integrated System ManualSection 2 Microwave Path Engineering Basics
Path Distance (d)
The path distance is the physical distance between the transmit and receive antennas. For the
TRACER 64x0, these distances can range up to 30 miles (48.27 kilometers).
System Losses (L)
System losses are defined by RF coaxial cable loss, connector losses, and losses added from any additional
lightning protection devices for the power budget an alysis. Coaxial cable is required to attach the TRACER
64x0 to the antenna. The length of the cable varies from a few feet to hundreds of feet, depending upon
your application and the proximity of the TRACER 64x0 to the antenna. Various grades of coaxial cable
will work sufficiently for connecting the TRACER 64x0 unit to the antenna. A low-loss coaxial cable will
minimize cable losses.
One end of the coaxial cable requires an N-type male connector (plug) to mate with the TRACER 64x0
unit. The other end of the coaxial cable requires a connector compatible with the antenna chosen for the
installation (usually an N-type male connector). Additionally, ADTRAN recommends that the outdoor
connector on the coaxial cable be weatherproofed to prevent corrosion and electrical shorting.
In areas wher e lightning strikes are frequent, a lightning arrestor should be installed
directly on the antenna coaxial cable. Installing lightning arrestors helps protect the
RF electronics (including the TRACER 64x0 unit) in the downstream path from
damaging voltages and currents.
Table 6 gives typical loss figures for some of the more common coaxial cable types (per 100 feet).
Table 6. Typical Coaxial Loss for Common Cable Types
Cable Type5.8 GHz Loss/100 ft (in dB) 5.8 GHz Loss/100 ft (in dB)
Section 2 Microwave Path Engineering BasicsTRACER 6000 Series Integrated System Manual
Path Loss (LP)
Path loss is the estimated attenuation between the transmit and receive antennas caused by signal
separation and scattering. The path loss is considered basic transmission loss over the microwave link. The
following expression calculates path loss:
4πd
⎛⎞
L
P
20 log
⋅=
--------- -
⎝⎠
λ
where
fcarrier frequency (Hz)
λcarrier wavelength (c / f) (meters)
dpath distance (meters)
cspeed of light, free-space (meters)
or
L
P
+=
96.620 log10d() 20·log+
where d is expressed in miles and f in GHz.
(dB)
⋅
10
f()
(dB)
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). Therefore, longer microwave paths naturally
experience more path loss than shorter paths. Likewise, higher frequency microwave communication
experiences more path loss than lower frequency microwave communication.
The path loss values for various path lengths for the TRACER 64x0 2.4 and 5.8 GHz systems are listed in
T able 7 (miles) and Table 8 on page 23 (kilometers).Values not listed in the tables can be interpolated from
those listed.
Receiver sensitivity is a value expressed in decibels referenced to one milliwatt (dBm) that corresponds to
the minimum amount of signal power needed at the receiver to achieve a given bit error rate (BER).
Receiver sensitivity is usually a negative number of decibels, and smaller receiver sensitivity (higher
quantity negative number) is better for a given BER. Several factors affect receiver sensitivity, including
the data bandwidth of the wireless link and the amount of additional signal degradation introduced in the
receiver electronics.
Receiver sensitivity of the TRACER 64x0 is dynamic as a function of the desired bandwidth; receiver
sensitivity improves as delivered bandwidth decreases. TRACER bandwidth is provided in the form of
eight channels available for mapping to the support modules. For T1 and E1 modules, each channel
mapped represents a single T1 or E1 interface. For Quad Ethernet Switch modules, each channel mapped
represents 2 Mb of Ethernet data delivered to the module. In situations where eight-channel connectivity is
not required, the delivered bandwidth can be decreased to four or two channels, and the receiver sensitivity
improves as follows:
4xE1 or 8 Mbps Ethernet-87 dBm-87 dBm
2xE1 or 4 Mbps Ethernet-90 dBm-90 dBm
TRACER 6410TRACER 6420
Should an interferer be present nearby, three software-selectable band plans are provided
for frequency agility. Changing the TRACER 64x0 band plan does not require additional
components or opening of the radio. See > RF Link Configuration > RF Band Plan on
page 64 for additional details.
Section 2 Microwave Path Engineering BasicsTRACER 6000 Series Integrated System Manual
6.ANTENNA INFORMATION
The overall wireless system is directly affected by the antenna selection and installation, discussed in the
following sections.
Verify the antenna installation meets all regulations specified in the National Electric
Code (NEC) Article 810 with particular attention to clearances from power and lighting
conductors, mounting, grounding, and antenna discharge unit.
Antenna Alignment
With line-of-sight microwave communications, optimum system performance requires that the
transmitting and receiving antennas are properly aligned. This ensures maximum received signal power at
each receiver. Antenna alignment must be achieved in both azimuth (along a horizontal plane) and
elevation (along a vertical plane). By ensuring maximum received signal strength, a received signal
strength indicator (RSSI) helps the equipment installer determine when alignment is maximized.
TRACER RSSI Test Points
RSSI for the TRACER 64x0 system is provided through the VT100 terminal menus accessed through the
RS-232 interface, and it is presented as a series of bars indicating signal strength. More bars means more
RSSI, which ensures greater received signal strength and better link performance.
If both the local and remote end of the system are operational, the remote TRACER 64x0 receive power
can be viewed from the local TRACER 64x0 VT100 terminal menu interface.
An RSSI test point located on the front panel provides a DC voltage level (relative to the
GND test point)
that corresponds to the amount of signal being received from the far end’s transmitter. The voltage at this
test point can vary from approximately 0 to 5 VDC. An RSSI calibration sheet is shipped with the system
to provide the installer a cross-reference between actual received signal level (in dBm) and RSSI voltage.
This sheet is useful for verifying link budget calculations and ensuring proper equipment installation.
Real-time Signal Values
The TRACER 64x0 system displays real-time signal values for RX QUALITY, RX POWER, and TX POWER
(for both the local and remote units).
with 0 corresponding to poor signal quality and 100 corresponding to exceptional signal quality.
RX POWER values are displayed in dBm within ±5 dBm accuracy and can vary with extreme temperatures.
TX POWER values are displayed in dBm within ±1 dBm accuracy.
Real-time signal values are not supported on all TRACER 64x0 systems. Systems must be
ADTRAN calibrated to provide readings for Rx or Tx Power signal levels.
RX QUALITY values are displayed as a numerical value from 0 to 100,
TRACER 6000 Series Integrated System ManualSection 2 Microwave Path Engineering Basics
Antenna Beam Patterns
Antennas used with the TRACER 64x0 system have a particular beam shape, determined in part by the
physical construction and geometry of the antenna. The antenna beam patterns are characterized by a
dominant main lobe, which is the preferred lobe to use for point-to-point communications, and several side
lobes, as shown in Figure 2. When setting up a microwave link, antenna alignment is nothing more than
steering the main lobes of both antennas until the main lobe of one transmitter is centered on the receiving
element of the receiving antenna.
main lobe
side lobes
Figure 2. Typical Antenna Beam Pattern
Antennas are also designed to radiate RF energy efficiently for a specific range of frequencies. Please
consult the data sheet for your particular antenna make and model to ensure that it is specified to operate in
the 2400 MHz to 24835 MHz (TRACER 6410) or 5725 MHz to 5850 MHz (TRACER 6420) frequency
bands for your TRACER 64x0 system.
Fresnel Zones, Earth Curvature, and Antenna Heights
Fresnel zones correspond to regions in the microwave path where reflections of the intended signal occur
and combine in both constructive and destructive manners with the main signal, thereby either enhancing
or reducing the net power at the receiver.
In general, the odd numbered Fresnel zones (1, 3, 5, ...) add constructively at the receiver, while the even
numbered Fresnel zones (2, 4, 6, ...) add destructively at the receiver.
The first Fresnel zone corresponds to the main lobe, 60 percent of which must be free of physical
obstructions for the path calculations to be valid. Since the main lobe contains the vast majority of the
microwave energy, this zone is typically used to determine proper antenna heights when placing antennas
on towers or buildings.
The curvature of the Earth becomes a legitimate obstruction for path lengths of 7 miles (11 kilometers) or
greater, and must also be accounted for when determining minimum antenna heights.
The aggregate expression for minimum antenna height that incorporates both the 60 percent first Fresnel
zone and the Earth’s curvature is given by
The path availability of a wireless link is a metric that expresses the fractional amount of time a link is
available over some fixed amount of time, and depends on several factors. Path availability is expressed as
The terrain factor is a quantity that compensates the link availability for different types of terrain.
Generally speaking, the smoother an area’s terrain, the less availability a wireless link running over that
terrain will have, primarily due to multipath reflections. In contrast, secondary 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 listed below:
TerrainTerrain FactorDescription
Smooth4water, flat desert
Average1moderate roughness
Mountainous1/4very rough, mountainous
Climate Factor (b)
The climate factor is a quantity that compensates the link availability for different types of climates
(weather). In general, microwave links operating in areas with high humidity will have less availability
than those in arid areas, primarily because water is a dispersive mechanism to microwave energy and
causes the main signal lobe to refract and disperse away from the receiver location. The climate factor
values normally used are listed below:
Section 3 Engineering GuidelinesTRACER 6000 Series Integrated System Manual
1.EQUIPMENT DIMENSIONS
The TRACER 64x0 integrated radio is 17.2 inch (43.7 cm) W, 11.4 inch (28.9 cm) D, and
1.7 inch (4.4 cm) H, weighs 7 pounds (3.18 kg), and can be used in rackmount configurations.
2.POWER REQUIREMENTS
The TRACER 64x0 radio has a maximum power consumption of 25 W and a maximum current draw of
1.1 A (at 21 VDC).
3.REVIEWING THE FRONT PANEL DESIGN
The front panel contains an RSSI monitoring interface, a GND interface for reference with RSSI, a TEST
interface for factory use only, a DB-9
interface (RJ-45) that provides an end-to-end serial port interface (at 9600 bps), and status LEDs to provide
visual information about the TRACER 64x0 system. Figure 1 and Figure 2 identify the various interfaces and
the LEDs for the TRACER 6410 and TRACER 6420, respectively. Table 1 on page 33 provides a brief
description of each interface.
CRAFT PORT for management and configuration, an AUX RS232