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Fringe Signal Reception

Ken — Sat, 18 Oct 2014 11:00:03 +0000

The other day I was helping my son move some things but in my rush forgot some crucial items. He was located in a near “dead zone” for mobile phone reception. Without a land line I had to depend on my cell phone that showed no “bars” of signal strength. Under these circumstances sometimes sending a text message will get through (see “A Texting Tale“). However, that doesn’t work with land lines on the other end.

Having spent a good portion of my career in the aerospace/defense industry I have spent some time around parabolic “dish” antennas and have applied this reflective principal to my cell phone on occasions.

Years ago I participated as an Assistant Scout Master at a camp. The parents of one of the Scouts helped transport our troop members and during the week took a vacation along the nearby California coast. At the end of the week they shared this experience with me. At one point the husband needed to make a call but had trouble finding a signal. He asked himself “what would Ken do?”. He looked for a parabolic feature in the landscape and found a rock with a concave surface. He placed the phone at it’s focal point and “bingo!” was able to connect his call.

I couldn’t find a signal at my son’s place so I found a pan and put my phone inside it. Surprisingly, even without a registered signal strength bar showing I was able to connect my call and have the critical items delivered.

This parabolic effect has worked for me and you might keep it in mind if you find yourself in a similar situation. I’m sure that there are other techniques that I would love to hear about so please share your successes in the comments section below so that we may all be better prepared for this eventuality.

A Texting Tale

Ken — Sat, 26 Nov 2011 12:00:15 +0000

Around midnight while I was fast asleep, there were two rings on the phone, then silence. Immediately I woke up and wondered if it was a wrong number, or was someone trying to contact me and was interrupted. My wife scurried to the phone that has caller ID and saw that it was my son’s phone number. He’s a big boy now, a junior in college, and I have bent his ear many times about safety measures and the need to walk in wisdom. He and his buddy had spent time in the mountains gaining a higher perspective over the town below, and when they began to descend, his buddie’s car ran out of gas. The cell phone signals are scant and difficult in that terrain.

My wife called his cell phone but was unable to connect, and could only leave a message on the automated voice mail. Remembering a blog that I once wrote “Text Messaging has it’s benefits…” I realized that a text message had the best chance of making the contact that we needed. While I texted we would get repeated calls that lasted a few seconds then silence. Although they were hard to hear and frequently interrupted, we got a sense of their situation. I completed the message and sent the text and bingo! a positive connection was established. I was able to get clear directions on where to meet and I was able to deliver gas and lend assistance in getting the car started and on it’s way to the nearest gas station.

So, remember, that when a regular call fails, text has the special properties of small bandwidth and “message persistence” that can get through when voice transmission fails.

Text Messaging has it’s benefits…

Ken — Thu, 22 Jan 2009 23:30:36 +0000

When you’re on the move or away from land lines, cellular phones are a tremendous way to communicate, providing that you can get a good enough signal. When using your phone, voice transmission uses a lot of power and drains the battery more quickly, thus jeopardizing long term use. When you experience marginal signal or your battery is low, text messaging is a great alternative for many reasons…

Text messaging uses “Short Message Service” or SMS provided with most digital cell phones. It operates with a “store-and-forward” mechanism that transmits to a Short Message Service Center or SMSC where it is relayed to the intended recipient. If the messages do not reach the recipient upon the first attempt, then the SMSC will try again. SMS delivery is not guaranteed but employs “best effort” delivery. The duration of this persistence varies with each phone company. It’s like posting an electronic note which does not require a conversation.

Because of the small bandwidth used, SMS has small character limits which have spawned “txt speak” like “CUL8R” (see you later), but in emergency situations, it’s best to not be cryptic. Also, a message can be composed and sent discreetly and silently if needed and has been employed by several rescued kidnap victims. There have been many reports that in the aftermath of Hurricane Katrina, when no phone calls were getting through, people were able to communicate through texting.

So next time you see “No Service” conduct your own experiment and try sending a text message and see if it gets through.