Surely you've experienced someone saying choppy ka during a conversation due to weak mobile phone signals. You might have even said it yourself a few times to the person you're talking to. Soon, however, that won't be a problem anymore.
The Defense Advanced Research Projects Agency (DARPA) and its A Mechanically Based Antenna (AMEBA) are trying to develop a portable ULF, or ultra-low-frequency (1Hz to 3kHz), and VLF, or very low frequency (3kHz to 30kHz) transmitters that are capable of penetrating any material that might be a hindrance to mobile phone signals.
This means that even the thickest wall won't be able to block your smartphone's signal. You can even talk while scuba diving if you really want to.
“If we are successful, scuba divers would be able to use a ULF channel for low bit-rate communications, like text messages, to communicate with each other or with nearby submarines, ships, relay buoys, UAVs, and ground-based assets,” according to a statement from Program Manager Troy Olsson.
“Through-ground communication with people in deep bunkers, mines, or caves could also become possible.”
If this innovation is made available in the country soon, then it'll be quite impossible to dodge phone calls from people you don't really like. We wonder what your excuse to skip the conversation will be.