CowChips HW2-TAG SPREAD SPECTRUM TRANSCEIVER User Manual USERS MANUAL
CowChips, LLC SPREAD SPECTRUM TRANSCEIVER USERS MANUAL
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USERS MANUAL
User’s Manual
NOTICE
The manufacturer reserves the right to make any changes and improvements in the
product described in this manual at any time and without prior notice.
This manual and the HeatWatch®II software are trademarked and copyrighted. All rights
are reserved. This document may not, in whole or part, be copied, photocopied,
reproduced, translated or reduced to any electronic medium or machine readable form
without prior written consent from CowChips, LLC.
Copyright © 2007 CowChips, LLC
TRADEMARKS
HeatWatch®II and HeatWatch® are registered trademarks of CowChips, LLC.
All other trademarks are the property of their respective owners.
PATENTS
U.S. Patent 5,542,431
FCC APPROVAL
This device complies with Part 15 of the FCC Rules. Operation is subject to the following
two conditions: (1) this device may not cause harmful interference, and (2) this device
must accept any interference received, including interference that may cause undesired
operation.
The user is cautioned that changes or modifications not expressly approved by the party
responsible for compliance could void the user's authority to operate the equipment.
FCC ID U8QHW2 - TAG
FCC ID U8QHW2 - CM
HEATWATCH II ESTRUS DETECTION SYSTEM
HeatWatch II takes advantage of the fact that standing heat is the most accurate visible
indicator for detecting cows and heifers in estrus. To monitor standing heat, HeatWatch
uses a small radio frequency (RF) monitor and pressure sensor attached to the tailhead of
the cow. The monitor sends information to a receiving/transmitting device called a base
station each time a cow is mounted. The information is stored in the base station and is
wirelessly transferred to another device called an access point which is connected to a
computer by way of a USB port. The stored data is automatically uploaded to the
computer when the HeatWatch II software is started.
Using sophisticated algorithms developed over the past 10 years, the HeatWatch II
software, running on a Windows based computer, analyzes the specific information
received from each cow and gives accurate information for cows displaying mounting
activity relating to estrus status and time to insemination.
HEATWATCH II EQUIPMENT
Monitors
Monitors, the heart of the HeatWatch II system are small, transferable battery-powered
digital radio frequency units containing a pressure sensor for detecting mounting activity
and transmitting this data to the base station. The base station will send a return message
to the monitor acknowledging its receipt of the data. If the monitor does not receive this
acknowledgment message, it stores that mounting data and re-sends it on a periodic basis
until the base station receives it. This would happen if a cow wanders out of range or is
behind a obstacle that would prevent a signal from being received by the base station.
Upon use, each monitor is enclosed in or attached on top of a patch that is glued to the
tailhead of a cow.
A monitor can transmit a mounting activity signal over a third of a mile in a line-of-sight
to the base station or repeater. Transmission occurs multiple times on multiple
frequencies over a 10 second period to ensure signal reception of mount data.
Periodically, a supervisory signal is sent from the monitor as confirmation that the
monitor is working properly. Should a monitor be in an active mode and not send a
supervisory signal, as in the case of a dead battery, you will be alerted by the software.
Each monitor has its own unique numerical identification code. No two monitors have
the same ID.
Monitor cases are constructed of hardened plastic designed to withstand mounting
activity forces.
The battery that powers the monitor is a 3.6 volt lithium battery. The device operates in a
temperature range of -40 to +140 F.
FCC site licensing is not required.
Base Station
The base station is a sophisticated electronic device that receives and stores mounting
activity information from the cow monitors in the form of RF signals. The information is
wirelessly transferred to the access point and into the HeatWatch II software. The base
station also sends signals back to the monitors acknowledging the receipt of mounts
and/or giving it certain instructions. The base station is encased in a weather-resistant
enclosure and is positioned in a line of sight proximity to the cows. The maximum
distance between the base station and the access point is a function of the types of
antennas used on both devices. The standard configuration will allow for 1000 ft.
The base station can be powered by either 110V outlet or 12V DC power.
Access Point
The access point receives mounting information from the base stations and passes that
information to the computer. The access point is connected to the computer and powered
by way of a high speed USB 2.0 cable.
Patches and Glue
A polyester patch has 3 functional components:
1. the base material used to affix the patch to the tailhead of the cow with Ruscoe
glue.
2. the nylon pouch that encloses the monitor, and
3. the tail strap that can provide retention of the patch and monitor to the cow if the
patch comes loose from intensive mounting.
The Ruscoe glue is a contact-type cement that has been used in the cattle industry for
years and is best known as Cattle Tag Cement. It is available in 10.5 oz caulking tubes.
Repeater
The repeater is a sophisticated transceiver which identifies signals from HeatWatch II
monitors and re-broadcasts those signals at full power. The repeater is used to relay
mounting information to the base station on large farms and ranches, or from area with
hidden mounting or heat detection locations. This effectively increases the range by
several miles in line-of-sight to the base station.
HOW HEATWATCH II WORKS
1. HeatWatch II is a reproductive management tool. When a cow is mounted, the
pressure sensor in the monitor on the tailhead of the cow is activated. Mount data
are transmitted the base station in multiple signals following a mount. The base
station, upon receiving mount data sends an acknowledgement signal back to that
monitor. If that monitor does not get the acknowledgement signal, it stores that
data for re-transmission at a later time. Supervisory data are transmitted at 60
minute intervals.
Note – Quantifiable mounts are usually distinguished from chin rests and other
activities. However, as with all information collection and management tools, the user
must exercise judgment in interpreting and validating data.
2. The base station accepts the mounting activity signal from the monitor.
3. The base station stores the mounting data and sends it to the access point when
the HeatWatch II software is started up.
4. The access point passes the mounting activity to the computer where the user may
observe mounting activity with the HeatWatch II software.
5. Through the integration of the mounting activity signals and the HeatWatch II
software, you can determine the best time to artificially inseminate or transfer
embryos.
6. It is recommended that the user back up data on a regular basis.
Lock-Out Specifications for HeatWatch® II Estrus Detection System
Data Protocol and Modulation
CowChips, LLC HeatWatch® II Estrus Detection System employs a proprietary spread
spectrum communications format that makes use of 25 independent channels in a 26
MHz block of frequency in the 902-928 MHz ISM band.
The cow monitor tag maintains timing synchronization with any base station or repeater
it is in range with and becomes the tags master.
Nominal HeatWatch II Link Specifications
System
Operating Frequency Range 902 – 925 MHz
Open Field Range 2,000 Feet (Rx & Tx 4’
above
ground)
Cow Tag
Operating Voltage 2.7 – 3.6 Volts DC
Operating Current 90 uA, idle
Transmitting current (30ms typical) 33 mA
Receiving current (30ms typical) 16 mA
Transmission Bandwidth 466 kHz (nominal)
Radiated Signal - Fundamental TBD @ 3 M, Peak
Radiated Signal - Harmonics TBD @ 3 M, Max.
(Averaged over 0.1 second
during transmission packet)
Base Station / Repeater
Power Requirements 11 – 14 VDC, 35 mA
Decode Sensitivity -109 dBm (from datasheet)
Spurious Emissions TBD dBuV/M, Max (Average)
Output 9,600 Baud Serial Data
Size 7½ in. X 5in. X 1½ in – 15oz.
(excluding antennas)
Access Point
Power Requirements 5V USB, < 200ma
Decode Sensitivity -109 dBm
Spurious Emissions TBD dBuV/M, Max (Average)
Output USB serial port
Size 5¾ in X 4¾ in X 1½ - 6oz ........
Architects/Engineers Specifications
The system implements a fully-supervised 900 MHz Spread Spectrum wireless
equipment. The wireless equipment utilizes a Frequency Hopping technique. Because
all communications are acknowledged, redundant messages are only required when a
message does not reach its intended destination. If a retry is necessary, a new frequency
from the pseudo random sequence is utilized. Repeaters support up to 16 hops.
In the event of a mount, a delay timer is started to in order to wait for the mounter to
leave the mountee. After the delay, the mounting activity is attempted to be delivered. In
the case of a long in activity (over an hour), the tag will find its host network and transmit
the mount data. If the tag can not find its host network, or it does not get an
acknowledgement, the mount information is stored and retries on a geometric scale
(longer time, longer time between reties). The tag can store up to 8 mount events with a
maximum mounting time of 63 seconds and track the delay in mounting up to 12 hours.
Supervisory messages are sent every 6 hours. A low battery signal is part of this
message. A low battery is sent when the battery level is ~2.6V.
The base station can store 60000 events. Evens are mounting activity or supervisory
information. The base station is also responsible managing all timing information in the
system, RF hopping timing and human time.