Radio Tracking Group
Our group is in charge of developing a tracking system that improves upon current solutions. The current solution for tracking the monkeys include darting the monkey, putting a radio transmitter collar on the monkey. The observer then tunes in that frequency with a radio receiver and listen for a blip. The hard part is actually telling where the monkey is. The user has to have some skill telling the direction of the blip. Tracking a the monkeys requires using a directional antenna with a radio receiver and listening for faint blips. The user then follows the strongest signal of blips until they can visually see the tagged monkey.
Our group Lisa Maria, Sonaar, Zeven and Russell want to create a solution that improves upon current technology. For starters, the current receiver require opening the unit up to change the frequency that the receiver listens to. This can be solved by purchasing any radio scanner (receiver). These radio scanners can scan through 50 frequencies a second and can be programmed to remember frequency such as those of the radio collars. These scanners are cheaper than the current receiver which cost around $800. A commercial radio scanner can be purchased for a $100 and have a lot more functionality.
We propose to improve current technology and instruments used to track wildlife. We will look into alternative telemetry receivers, antennas and tagging transmitters. We will test and compare current instruments to different alternatives.
One of the open questions we talked about in class was a way to remotely monitor the monkeys. One of the solutions that I thought would work is establishing radio antenna stations throughout the observation area. These antenna stations could sense when a tagged monkey enters it's range and either log or relay that information back to base camp.
Having the antenna stations logging when they detect the tagged monkey would be the simplest form of passive tracking the monkeys. The data logged can then be used to triangulate the location of the tagged monkeys.
We looked into energy densities.
We wanted to know if it would be possible to use other elements as a power source. We looked into using hydrogen peroxide or an alcohol such as methane, or ethanol. These alternative fuels have a denser energy mass then does the best battery technology. The one thing these alternative fuels will need is a motor generator to turn the fuel into electricity.
Research in Tracking Animals
Telemetry Receivers and Consumer Receivers - Round 1
Our group began looking into using consumer grade radio scanners (receivers). They are a lot cheaper then the current telemetry specific receivers. There are pro's and con's to each type of receiver. The consumer receivers are cheaper and can be purchased at any electronic store. They offer a lot of features, such as communication with a computer and GPS integration.
The tradeoff of the consumer radio scanner is they do not have a high sensitivity for picking up faint radio signals. The specific animal tracking scanners (telemetry receiver) can receive the faintest of transmitter beeps. Having a sensitive radio allows the user to hear a signal from a weak transmitting transmitter. The sensitivity of a consumer radio scanner is around 0.4 microvolts. A telemetry receiver has a sensitivity around 0.007 microvolts.
We tested the consumer radio scanner and a the telemetry receiver to see if there is a noticeably difference in sensitivity. We put both receivers next to each other and had a transmitter collar laying across both antennas. The collar had a very weak signal due to a low battery. The telemetry receiver was able to receive the pulse from the collar while the consumer receiver just heard static noise. The test didn't have to go any further. It was clear that the consumer receivers would receive the transmitter collar's signal when battery is fully charged, but overtime the consumer receiver could not detect the faint signal of the radio collar.
Telemetry Receiver vs. Uniden BC346XT - Round 2
Taking the advice from Eric Rosenthal we retested the Uniden radio receiver against Tony's telemetry radio receiver. We setup the Uniden by turning off all the auto features and manually controlling the frequency stepping. We used the good collar which has a frequency of 148.500 MHz. The setting that Eric Rosenthal recommended were set in the first round of testing and remained for this test. The only change was we set the radio to manual mode instead of automatic. The second test mimic the first. We set the collar at a fixed position while I walked away from the collar with the telemetry receiver and the Uniden receiver in my hand. One curious fact that we found in conducting the test was stepping the frequency higher and lower from the base of 148.500 MHz proved to increase the reception of the signal as we increased distance from the collar. We stepped the frequency .1 KHz on the telemetry receiver and we stepped the frequency 10 KHz on the Undien (this is the minimal step increment for the Undien). When I heard the signal dying off I would increment up and down the frequency to improve reception. This was affective for the telemetry receiver but doing the same to the Uniden did not result in a better reception. Both receiver received a clear signal for about 300 feet. After 300 feet the Uniden receiver began to lose the signal as I walked further away. In short the first test that Zeven and Russell conducted were accurate. The settings that Eric suggested were indeed what we had configured for the first test.
No change, the Uniden scanners won't work.
Using XBee 900's for Wildlife Tracking
We wanted to find out if XBee 900's could be used as tracking system. Our first test took place at Washington Square Park. We used two XBee Pro 900 RPSMA. Monkey XBee was fitted with a Digi 2 dBi 7 inch omnidirectional antenna. The trackers XBee was also fitted with the same omnidirectional antenna. One person stayed with the trackers XBee at Washington Square Park, while the other person walked north on Fifth Avenue with the monkey XBee. We were able to get a range of .48 kilometers or 1/3 of a mile with the omnidirectional antennas. We then changed the trackers antenna to a 12 dBi Yagi directional antenna. Using the Yagi antenna increased our range marginally. We were able to get an additional .09 kilometers or 300 feet from the Yagi. We did use the Yagi antenna to increase range but to locate the direction of the monkey.
The second was at Central Park. We repeated the first test to see if the trees and foliage changed our results compared to the urban environment of Washington Square Park and Fifth Avenue. The range was similar to urban test, the real issue is radio interference. We observed packet loss with the XBee's. This issue is a characteristic of a highly sophisticated networking protocol. Our conclusion was the XBee's are not a suitable solution for replacing the current analog tracking system.