Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Using Mobile Phone Dialling Signal Locally

Status
Not open for further replies.

madhavjj

New Member
This thread is for investigating if we can use the dialling signal sent out by the mobile cell phone locally.

For Example : Suppoe we enter 4 digit number say 2311 on our mobile and press dial button on the phone, our cell phone sends out some signal to the nearest base station tower.
Since this 4 digit code is probably meaning less from the point of veiw of the service provider, it responds by saying " Number dialled by you is incorrect. Please check the number."

Now the question is, can we ourselves, locally detect this transmission which was sent out by our cell phone and make some use of it ? There are many possible uses of this facility.

May be we have to design and build a local base station of our own which will do this job. May be we will also need a suitable antena to receive this weak signal from the cell phone.

But is it possible ? Certainly it is.

This process is being carried out by millions of cell phone towers acrosss the world. Can we use their ready made proven hardware designs , 'as it is' or in a miniature small scale level for our personal private use ?


Please suggest circuits or methods to do this.
 
Last edited:
In a word. NO.
PS bad idea to post your email & phone in a public forum.
Dear Blueroomelectronics,

1.I am sorry my contact details appeared under the message. I do not know how they came there. I have registered on this forum about two years ago but I am using it for the first time to get some help. I still don't know how I can remove this personal contact information from the thread post. Please tell me how.

2. As regards the thread. Can you briefly explain why this will not work ? With your reputation I certainly believe you but all the same I have a curiosity to know why. Please give short technical reason for the same.

Thank you in advance for your kind help.

Madhav Joshi
 
I make vehicle tracking devices that use cellphones. That doesn't mean that I know much about how cellphones work, just that I know how to use some features on them.

The way that cellphones communicate with the cell towers is incredibly complicated. Just to give you some idea here are some details on the way that they work.

When numbers are dialed, the digits are not sent separately, one after the other like the DTMF tones on a landline. A data burst is sent with all the dial information.

The frequency and power of the transmission will depend on what tower the phone is talking to. It can change during a call as a call can be handed from one tower to the next.

I am fairly sure the number is encrypted. The voice or data is certainly encrypted.

The phones do not transmit all the time, even during a call. They only transmit for 1/8th of the time, 216 times a second. So there is a burst that is about 570 µs long, every 4.8 ms. If there is another cellphone near, it may be transmitting on the same frequency, but in a different time slot.

The timing of the transmissions from the cellphone is varied so that all the transmissions on one frequency (up to 8) will arrive at the tower at different times. If a receiver is somewhere else, some transmissions may arrive at the same time.

The result is, if you want to get data from a mobile phone, use it the way it is suppose to be used.
 
Dear Diver300,
Thanks a lot for some insight in technical complexity. I did not know much of it.
I will like to give up the thought at this stage. However one small ray of hope :

All this complex process is being handled trillions of time in a day by few million towers across the world. Can we not borrow some ready made hardware or circuitry from them and do the same on a small or micro scale basis in our own drawing room for our own personal use ?

I will still keep my eyes open if you can give me some positive lead on this please.
 
All this complex process is being handled trillions of time in a day by few million towers across the world. Can we not borrow some ready made hardware or circuitry from them and do the same on a small or micro scale basis in our own drawing room for our own personal use ?

You would presumably require a telecom licence, and LOT'S of money to buy the expensive hardware required.
 
You would presumably require a telecom licence, and LOT'S of money to buy the expensive hardware required.
1.Yes. I think you must be right.

2. Since I have got absolutely negative response from two very reputed boarders I will like to close this thread.

Thanks for the help.
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top