Homeland Security Broadcasting System (HoSBroS)

Excerpt from the patent specification:


The HoSBroS system provides a radio frequency receiver equipped with a noise gate which can be embedded in virtually any consumer electronic device.  Initially, wireless audio devices such as smoke detectors and radios are the most desirable point of implementation.  Thereafter, any consumer electronic device that includes or drives a digital video display or audio output device, such as a computer, television, VCR, DVD player, cellular phone, pager, wristwatch, wall or desk clock, microwave oven, automobile clock or onboard navigation system, or personal digital assistant (PDA) can be HoSBroS-enabled.

The system also includes radio frequency transmitters which can be used by police or local governmental agencies to broadcast emergency messages at a variable level of signal power, so that such emergency messages can be targeted to a single city block or broadcast across an entire metropolitan area.

When a HoSBroS-enabled consumer electronic device receives a signal strong enough to open the noise gate, the typical function of the device is overridden so that the device outputs the emergency message.  Thus, information vital to the survival of citizens imperiled by an emergency can be conveyed immediately and specifically to them via almost any electronic device that is still functioning in their environment.


This system was created immediately after and in response to the events of September 11, 2001.  My understanding from reports at that time was that some victims could have escaped if there had been a way to communicate with them so as to let them know of viable escape routes.  My understanding of the challenges included:

  • first responders not knowing who was actually at a given location at a given time, i.e., who the people in the crisis situation were
  • first responders not knowing the phone numbers of people who were in the crisis situation such that, even if a given crisis victim were known to be at the location and to have his or her cell phone available, the person still couldn’t be immediately contacted
  • first responders not being able to communicate with those in the crisis situation via conventional loud-speaker means (e.g., bullhorn) because of physical distance, obstructions, or ambient noise

The original system (above)—being based on the rather blunt “noise gate” feature—was thereafter redesigned so as to use GPS to target all phones and other electronic devices falling within a set of GPS coordinates associated with the emergency.  This latter approach appears to have been at least partly embraced by smartphone makers and the U.S.’s “Amber Alert” system.  I’m not sure whether any other devices (e.g., fire alarms) have yet been so enabled.

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