R
Resistense
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Here is a portable, Lithium-ion powered transmitter.
Spektrum - NX8 8-Channel DSMX Transmitter Only, Radi… $350 U.S. at Horizon Hobby. __https://ww__w.spektrumrc.com/Products/Default.aspx?ProdID=SPMR8200
From the last page in the manual (uploaded as SPMR8200):
Frequency Range and Wireless Output Power:
Control and Trainer: 2402-2478 MHz / WiFi: 2412-2462 MHz
Control: 18.7 dBm / Trainer: 1.43 dBm / WiFi: 18.5dBm
So, 18.7 dBm(decibel-milliwatts) from the transmitter is 74.13mW(milliwatt) power output. . Frequency in the range of 2402-2478 MHz.
On the DSMX technology:
From Wikipedia on spread spectrum, and the first section, "telecommunications":
Just more documentation that this could be done remotely. Will try out some math for the power density level if I can define the variables. Although it could only work if it's hooked up to an airplane...
Spektrum - NX8 8-Channel DSMX Transmitter Only, Radi… $350 U.S. at Horizon Hobby. __https://ww__w.spektrumrc.com/Products/Default.aspx?ProdID=SPMR8200
From the last page in the manual (uploaded as SPMR8200):
Frequency Range and Wireless Output Power:
Control and Trainer: 2402-2478 MHz / WiFi: 2412-2462 MHz
Control: 18.7 dBm / Trainer: 1.43 dBm / WiFi: 18.5dBm
So, 18.7 dBm(decibel-milliwatts) from the transmitter is 74.13mW(milliwatt) power output. . Frequency in the range of 2402-2478 MHz.
To calculate that power output density (with dimension unit) we'd have to know the "gain" of the antenna (which I think depends on beam steering), and the distance to (and size of?) what the telemetry is zeroed in to transmit toward, the receiver."...average incident power density level of about 0.1 mW/cm2 and a peak intensity near 300 mW/cm2. [...] frequency range of 200-3000 MIHz and for pulse widths from 1-100 (micro)s”47.
[...] RF/MW in the 2.4-10,000MHz range45
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On the DSMX technology:
The NX8 transmitter is built around proven Spektrum™ DSMX® 2.4GHz frequency-agile technology — the most advanced spread spectrum RC technology to date. By adding the agility of unique frequency shifts to the superior interference resistance of a wideband signal, and by limiting those shifts to a smaller portion of the 2.4GHz band, DSMX® transmitters provide on-channel interference protection that’s second to none.
From Wikipedia on spread spectrum, and the first section, "telecommunications":
So, DMSX transmitters provide on-channel interference protection (to resist communications jamming), or, could transmit information with pulse modulation, since there's a low probability of intercept unless the receiver is actually linked up to what the transmitter is doing, or you have a very nice field spectrum analyzer.Spread spectrum:
In telecommunication and radio communication, spread-spectrum techniques are methods by which a signal (e.g., an electrical, electromagnetic, or acoustic signal) generated with a particular bandwidth is deliberately spread in the frequency domain, resulting in a signal with a wider bandwidth. These techniques are used for a variety of reasons, including the establishment of secure communications, increasing resistance to natural interference, noise, and jamming, to prevent detection, to limit power flux density (e.g., in satellite down links), and to enable multiple-access communications.
Telecommunications:
Spread spectrum generally makes use of a sequential noise-like signal structure to spread the normally narrowband information signal over a relatively wideband (radio) band of frequencies. The receiver correlates the received signals to retrieve the original information signal. Originally there were two motivations: either to resist enemy efforts to jam the communications (anti-jam, or AJ), or to hide the fact that communication was even taking place, sometimes called low probability of intercept (LPI).[1]
Just more documentation that this could be done remotely. Will try out some math for the power density level if I can define the variables. Although it could only work if it's hooked up to an airplane...