According to Navsys, the company that developed JLOC, it involves a network of GPS receivers capable of detecting regions of higher than normal signal levels and low signal-to-noise ratios, either of which can indicate interference.

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While riding the bus, my cell phone signal suddenly went out, which is not normal, and continued to search for a signal for 15 minutes.

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Nemesysco's devices use a series of patented signal-processing algorithms that can differentiate between a "normal" voice and a"'stressed" voice.

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However, both price-to-cash earnings and price-to-sales are currently sitting within the historically normal valuation levels, so it is sending neither an Undervalued nor an Overvalued signal.

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No matter what part of the normal radio spectrum you pick, you will find some material that will reduce, deflect or block the signal entirely.

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