Installation Guide for the CTT SensorStation and CTT Nodes
In order to connect directly to your SensorStation, you’ll need 2
USB->Ethernet Adapters (we recommend: https://tinyurl.com/yc6llze4), and an Ethernet Cable, or
Raspberry Pi compatible USB WiFi adapter like this one https://store.celltracktech.com/products/wifi-usb-adapter-add-on-for-sensorstation-v2.
Make sure to have these on-hand prior to receiving your
SensorStation so there is no delay in setup.
As of June 2022 we have released the 3rd version of the SensorStation. V3 SensorStations differ from V2 stations in a few important ways.
This User Guide has been redesigned around the new (ca.2020) Version 2 SensorStation (V2) which includes an LCD display. Otherwise, Version 1 stations (ca.2019) are nearly identical to V2 stations. In cases where they differ, we have made note in the manual. If you are setting up a V1 station you may want to begin at the QuickStart Guide in Appendix II. If you find inconsistencies in this manual please email us at email@example.com as we will be updating the manual regularly.
We now have a
Slack workspace dedicated to CTT users.
Topics range from station logistics to study design, and from data
management to current development of novel analytic tool. Come be a part
of the discussion and engage with other users as we push the boundaries
of remotely sensed telemetry data! Click here to
request access to our free and vibrant Slack workspace.
If you are reading this document, then you most likely have purchased one of our Internet of Wildlife (IoW) components. Whether you’re doing localized detailed studies of small mammals or songbirds, or you’re setting up SensorStations as part of the global Motus Wildlife Tracking System (motus.org), or you’re doing something in-between, we’ve got you covered, and this document is meant to help you get started quickly and painlessly. If for some reason you get stuck along the way, please don’t hesitate to reach out to us directly either via email (firstname.lastname@example.org) or through our online Help Desk here: https://celltracktech.com/support/.
If you are setting up your SensorStation to participate in the Motus Wildlife Tracking System (motus.org), your station can still be used with CTT Nodes. In general, we recommend Motus stations to include 4 Yagi 10-element antennas pointing in the 4 cardinal directions. A fifth Omni antenna can be installed and dedicated to detecting nodes, or one of the Yagi antennas can be used for nodes while the other three are positioned at 120 degrees for full coverage. You may also add any number of 166MHz antennas by using a Software Defined Radio (SDR), such as a FunCube or RTL-SDR, via any of the USB ports on the SensorStation (SDRs are sold separately via third-party companies). A clear view of the horizon is preferred to get maximum range, so a height as high as possible is also advised. For more information on Motus, see Appendix I.
Treat your SensorStation board like you would any other motherboard, Arduino or Raspberry Pi. All electronics, no matter how robust, can be static sensitive. Take care no metal objects touch the board while it is operating, such as antenna connectors or GSM antennas, as this could cause electrical shorts that will damage the board. It is advised to wear an anti-static bracelet when handling SensorStation.
CTT’s Internet of Wildlife System (IoW) is a complete radio telemetry system that consists of transmitters (radio tags), and receivers. Currently CTT produces five radio transmitters: the LifeTagTM, PowerTagTM, HybridTagTM, ES-200 and ES-150.
The CTT LifeTag is 100% solar powered, and therefore
has no battery. This allows the tag to persist for many years, beeping
out its unique digital ID whenever it has sunlight. For species active
during the day, and for small animals for which multi-season or
multi-year data are required, LifeTags are the obvious choice. The
LifeTag coding includes a CRC value that validates
detections on all
V2 SensorStations, reducing the chance of
any false detections by over 99%.
The CTT PowerTag is battery powered which means it
can beep out its digitally coded ID 24-hours a day. The life span of a
PowerTag is defined by the beep rate (# of beeps per
minute) and battery size. For nocturnal species,
are the perfect fit.
The CTT HybridTag takes the best features of our
PowerTag and combines them into
the smallest fully rechargeable radio transmitter in the world. With as
little as 30-minutes of solar exposure over three days, the HybridTag
will maintain its battery charge indefinitely. The
HybridTag can be turned off and on using a small magent
place on the underside of the tag. In the absence of any solar exposure,
HybridTag battery can power the tag for anywhere from
36 hours to over two weeks (depending on battery size). The
HybridTag employes the same CRC validation as the
LifeTag meaning that your detections are over 99%
The ES-200 and ES-150 are GPS
logger tags that can also send data over the 434MHz frequency, and
therefore can send archived telemetry data to the
SensorStation. Since they communicate on the same frequency
as the smaller radio tags, no special radio configuration is needed. The
difference between the two is that the
ES-150 also has an
Argos radio to send data via the
The CTT SensorStation collect data directly from
tags and can collect data from a series of
Nodes to more
precisely locate tags within a study site. The
SensorStation stores data and, with an optional GSM data
plan, can also send those data directly to the CTT and Motus
CTT Nodes are essentially mini-base stations: devices with integrated solar panels, a lithium battery, and an antenna to collect data from PowerTags, LifeTags and HybridTags, and send those data to the SensorStation. These data can then be post-processed to localize tags within a grid of nodes over user-defined time steps.
The detection distance from Node to Tag varies for various reasons, including terrain, vegetation, and the behavior of the tagged animals. For instance, a bird flying overhead may be picked up over a kilometer away by a node, but one foraging in dense vegetation may only be detected from a few hundred meters. When using nodes for localization it’s important to note that the accuracy of locations of animals wearing tags can be as little as 30m, but can range widely depending on the density of Nodes. For localizing tag positions, the spacing and placement of nodes must allow for tags to be detected simultaneously by three or more nodes.
The detection distance from SensorStation to Node is
also affected by terrain and vegetation, but also antenna height and
type (omni-directional vs. directional). Therefore, while there
is no hard and fast rule, a good starting point is to keep your farthest
node within 1-1.5km of the SensorStation. The number of
SensorStations needed for each system depends on the size of the study
area. For instance, in a 2 KM2 plot, a SensorStation placed
at the center of the plot could detect nodes across the entire study
area, in most cases with only an omni-directional antenna. Because
Nodes are dependent on the SensorStation to receive their
data and aggregate it for analysis, it is critical to ensure each node
is within the detection radius of at least one
SensorStation at all times.
The detection distance from SensorStation to Tag is affected by the same factors as SensorStation to Node, but because many tags are on birds, bats and insects, the relationship between the two objects can change drastically over very short time steps. With line-of-sight, a tag on a bird has been shown to be detectable for dozens of kilometers by a SensorStation. On the other hand, birds foraging in dense vegetation may only be detectable by a station within a few kilometers. Therefore, careful consideration of station position with relation to the biological questions being asked is critical for a successful deployment.
For both the SensorStation and Nodes we recommend attaching to EMT conduit. We recommend this because it is rigid and easy to set up. This is not what’s commonly referred to as Black Pipe used for water and gas lines, but the galvanized steel pipe used for running electrical wiring inside.
We don’t recommend PVC because it moves in the wind, becomes brittle, and will snap over time. EMT can be painted if you would like them camouflaged.
The conduit can be attached to a tripod, mounted directly into the ground, or onto a building or other structure. The Nodes and SensorStations are then attached to the conduit. The diameter of the conduit is typically 1” for the top mast section of the SensorStation (the section to which the antennas are attached; light green in the picture below).
For every 7 feet of height the base section will increase in diameter by ¼”. For example, in the picture above, a 15 foot mast will have a 1” section (light green) inserted into a 1 ¼” (orange) and then into a 1 ½” (blue). If the conduit is inserted into the ground, the 1 ½” conduit should be inserted into a 4’ section of 2” pipe (dark green). The pipe in the ground is cut in half, the bottom flattened slightly with sledge hammer to keep soil from entering when it is driven into the ground. A block of wood can be used to pound the pipe into the ground to prevent bending the pipe. If the antenna mast is shorter, the next size up gets driven into the ground (1/ ¼”). Note that standard EMT conduit does eventually rust, however it will remain very strong for 6-10 years.
If desired, stainless conduit can be purchased, however it is much more expensive, but recommended if you are in an area that receives high winds. It is crucial to overlap each section of pipe by at least 2 feet. Self tapping screws are used to hold pipes together, but should not be used within 3-4” of the end of the pipes and/or seams. The chart below should help with what is needed for your setup per SensorStation.
|Total Approx Mast Ht.||EMT Needed for mast (10’)||Ground Section Needed (4’)||Coax Length Per Antenna|
|7’||1”||1 1/4”||min 10ft|
|15’||1”,1 ¼”||1 ½”||min 20’|
|23’||1”, 1 ¼”, 1 ½”||2”||min 25’|
|28’||1”, 1 ¼”, 1 ½”||2”- Use full 10’||min 30’|
Masts higher than 28’ not recommended with standard free-standing EMT conduit. Guy wires and/or scaffold or tripod masts are other options for higher towers.
Nodes are typically attached to the top of a ¾” piece of EMT. The clamps shown below come standard with the nodes and accept ¾ or 1” conduit.
A 7/16” socket is used to tighten the clamp bolts. The EMT is typically driven into the ground approximately 2 feet. The height of the nodes can be changed depending on the project, but for best results should be consistent within a study site. We recommend 8’ for most setups, see below for pictures of the node setup in the field. If you choose an alternate mounting method, care should be taken that they are secure. If they are mounted on anything that sways greatly with the wind, the readings won’t be consistent.