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Livestock Monitoring
Brenda Land, Project Leader
Features of Unit Tested
The Lotek GPS_2200L collar
integrates a VHF beacon transmitter with a GPS datalogger and sensor. The
collar was designed for use primarily in tracking mid-sized wildlife such
as deer, wolves, bears, and large cats. An "R" version is available, which
differs only in its smaller battery (and duty cycle) and overall size.
The unit tested was a modified version of the "L," referred to as an "L(R),"
which has a rechargeable lithium-ion battery in a slightly larger housing.
(See table 1.)
Table 1—Specifications of Lotek GPS_2200 collars.
| Specifications |
Model |
| GPS 2200R |
GPS 2200L(R) |
| Housing Dimensions (cm) |
Length x Width x
Height |
12.0 x 8.6 x 10.5 |
12.0 x 8.6 x 12.6 (14) |
| Belt Weight (g) |
Heavy Duty; e.g., wolf |
800-850 |
900-950 |
| Light Duty; e.g., deer |
750-800 |
880-920 |
| GPS Battery Life |
Total # of Fixes |
4000 |
9000 |
| @8 Hour Fix Schedule |
365 days |
> 2 years |
| VHF Beacon Life |
> 2 years |
| Data Storage Capacity |
Nondifferential |
10,423 locations |
| Differential (optional) |
5,028 locations |
| VHF Range (frequency hardwired when assembled) |
140 to 220 MHz |
| Operating Temperature Range |
-30 to +50 °C |
| Data Retention Range |
-50 to +75 °C |
| Optional Sensors |
Temperature, Mortality, Recovery, 2-Axis Activity |
| Field Replaceable Battery Pack |
Yes |
| Field Programmable |
GPS & Beacon Schedule, Mortality Delay
|
| Field Upload |
GPS & Beacon Schedule, Satellite Almanac, Mortality Delay |
| Field Download |
Data & Diagnostics |
Key hardware features of the tested GPS_2200LR include:
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VHF Tracking Beacon—The collar
emits a beacon, which facilitates tracking and collar retrieval using conventional
tracking techniques. The beacon also indicates the status of the collar
by emitting a variety of pulse rates for different conditions (e.g., normal,
dead battery, recovery, mortality). Beacon broadcast frequency is user
specified and hardwired at the time of assembly.
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Battery—The lithium-ion battery
is rechargeable and field replaceable. A fully charged battery is capable
of recording up to 9,000 position fixes, for over a 2-year period, depending
on the frequency of position fixes.
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Data Storage—The capacity for
data storage is more than 10,000 position fixes.
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Housing—The housing is made
of high-impact resin, with high tensile strength, and high and low temperature
resistance. The unit is waterproof to a depth of 10 meters.
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Collar—The collar integrates
the GPS antenna into an adjustable strap. The antenna itself sits, nonprotruding,
on the top of the collar strap for maximum signal exposure. The belt is
foam padded and adjustable from both sides to center the antenna.
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Electronics – The unit's operational
temperature range is from -30° to +50° C (which is better than
that of the sheep).
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The following options are available
to customize the units:
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"Activity" Sensor (not tested)—The
two-axis activity sensor detects and records "active" verses "resting"
animal states.
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Temperature Sensor (not tested)—The
temperature sensor records ambient air temperature.
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Differential Correction (not
tested)—The differential correction collects and records position fixes
so that accuracy can be further improved through post-processing. (It also
requires an operational base station and additional Lotek N4WIN software.)
-
GPS Scheduler—This scheduler
allows modification to the default frequency of position fixes. A "basic"
scheduler (tested) allows a single change to the default frequency of position
fixes (e.g. every 4 hours or every 2 hours through the period). The "advanced"
scheduler (not tested) allows extensive control with scheduling position
fixes (e.g. every 30 minutes from 8 a.m. to 8 p.m., and every 2 hours from
8 p.m. to 8 a.m., or every 2 hours from June 1 - August 1 and every 4 hours
from August 1 to October 1).
-
VHF Beacon Scheduler (not tested)—This
scheduler allows modification to the default beacon operational schedule
(i.e., 8 a.m. to 5 p.m.).
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Programmable Mortality Setting
(not tested)—The programmable mortality setting allows modification to
the default mortality delay (8 hours); (i.e., animal time at rest before
transmitting the mortality/recovery signal).
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The unit requires the use of
Lotek software (GPS_2000 Host). The MS-DOS-based software accommodates
the full options and sensors available with the GPS_2200 unit. With the
included cables and "download link unit", the software facilitates launching
the units, and subsequent retrieval of the data. The download link is battery
powered (rechargeable) to facilitate downloads to a laptop in the field.
Finally, the package as tested
also included all the tools and products for successful deployment including
recharge kit, O-rings, sealant, special screws, and even a torque nut driver.
(See table 2.)
Table 2—Cost of Lotek collar as tested (GSA, August 2000).
| Product |
Cost |
| GPS_2200L(R) Collar (each) (includes basic GPS_2000 Host software) |
$2,328 |
| Recharge kit |
$97 |
| Download link |
$728 |
| Torque nut driver |
$165 |
| Basic scheduler |
$291 |
| Total |
$3,609 |
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