When the chip is hit with a radio frequency signal, it emits a unique identifier number that functions like a long, unguessable password.
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And since a moving object causes a tiny change (known as a Doppler shift) in the frequency of the reflected signal, Silent Sentry can also calculate how fast it is moving.
Simply stated, single-frequency networks are when a broadcaster uses multiple transmitters to send the same signal over the same frequency.
The FM radio's scanner "found" a station at virtually every legal frequency, even when no signal was present--as well as several channels unusable in North America.
On channel boosters quickly receive the OTA signal from the main tower and retransmit the signal on the same frequency.
The superconductor's lack of resistance allows the firm to build filters that can chop a signal into much narrower frequency bands than a traditional filter.
The cylindrical speaker features two high-performance drivers, a built-in bass port and digital signal processing software to extend frequency response on the high end while providing tighter low ends for deeper bass response.
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The higher up you go in the frequency range, the less robust the signal is and the more repeaters you are required to use to propagate your signal so that it can reach and penetrate buildings.
Only a receiver programmed with the same random sequence would be able to follow the signal as it hopped from one frequency to another.
Patriot missile components including advanced radar waveguides, microwave devices, high-speed analog to digital converters, microprocessors, precision gimbals for the missile-seeker system, highly miniaturized radio frequency communications, on-board sensors, advanced signal-processing systems.
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In an announcement of sorts yesterday, DARPA reportedly said that the project's goal is to use "set of handheld devices" to track down a specific "signal emitter of interest" using radio frequency geolocation, and presumably some other measures they're not about to dish the details on.
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Power companies and networking startups have spent years touting a technology called broadband-over-power lines, or BPL. In those systems, the utility sends a data signal across existing wires at a much higher frequency than electricity, so the two signals don't interfere.
They emitted so much radio-frequency interference that Mr. Clark struggled to get a clear signal for the band's wireless instruments and in-ear monitors.
Furthermore, the LightSpeaker's 2.5-inch wide dispersion driver uses digital signal processing to optimize high- and low-frequency output for a full spectrum of sound.
The device recognizes a signal that is "hidden" in a broadcaster's frequency and automatically sends the information back to Arbitron every night.
Unlike the repeater towers that are sometimes used in western states (AKA translators), SFNs aren?t simply receiving the signal, error-correcting, and retransmitting on a different frequency.
The best part is, applying different levels of OAM twist to SAM-based transmissions theoretically allows an infinite number of streams per signal, meaning seriously increased bandwidth without the need for additional frequency.
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With HackRF in the hands of hackers or security researchers, in other words, no wireless signal would remain secure just by virtue of using a unique, unfamiliar frequency.
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Then through the use of GPS-based reference clocks at each tower (for both time and frequency), the signals are synced so each can emit a perfect copy of both signal and symbol data.
It's like 'inverting' the signal on odd lines, or shifting it in time by 180 degrees of the color waveform frequency.
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Battery power consumption depends on factors such as network configuration, signal strength, operating temperature, features selected, vibrate mode, backlight settings, browser use, frequency of calls and voice, data and other application usage patterns.
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