I'd like to see all phones and phone towers fitted with an emergency ping ability and an emergency ping protocol, since almost everyone carries a phone these da

I'd like to see all phones and phone towers fitted with an emergency ping ability and an emergency ping protocol, since almost everyone carries a phone these days. If you needed help, you'd enter a text describing your situation (a default text would be used if you could only click a "HELP!" button), put the phone in a special mode that would shut everything down to conserve battery power but would send out a stronger-than-usual radio "ping" every 60 seconds or so (depending on battery). To save energy, the ping would not include the text. The repeated pings would be optimized to just shout into the ether, to get attention from the greatest distance possible. Any receiver would recognize that it was an emergency ping and could respond with a protocol response ping that requested more info. The response would be sent at a predefined time delay and frequency that would be determined by the outgoing request ping that had been received so the phone would only have to listen to one frequency and for a brief time to save battery. The phone could rotate its outgoing pings to different frequencies but would always know when and at what frequency to listen for a response based on the outgoing ping it sent. When it got a response from a tower, and only at that point, the phone would expend extra energy to transmit its location, the text, battery status, etc. Based on various factors, the tower would schedule future transmissions and automate most of the data exchange to conserve the phone's power, would notify responders, and would tell the phone to notify its owner that help was being sent. You could then put this emergency ping protocol into search and rescue aircraft and drones with mesh network abilities.