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Hi Chris

I am trying to construct a server whereby it can be able to receive information and detect the location of a particular wireless signal.

I have a product which is worn on the hand of a person. It is suppose to be able to detect the pulse rate of the particular person and if this pulse rate exceed the "critical pulse rate" set in the program, it will transmit a signal through wireless to the server. The server would then tell the location at which this signal is send from and show the information of the person.

The problem is that I do not know how this server could be set up. Could you help?

Thanks

Calvin

Hi Chris

I am trying to construct a server whereby it can be able to receive information and detect the location of a particular wireless signal.

I have a product which is worn on the hand of a person. It is suppose to be able to detect the pulse rate of the particular person and if this pulse rate exceed the "critical pulse rate" set in the program, it will transmit a signal through wireless to the server. The server would then tell the location at which this signal is send from and show the information of the person.

The problem is that I do not know how this server could be set up. Could you help?

Thanks

Calvin

Hello,

This should not be to hard to do. However there are a lot of different issues you will need to address.  More then what I can comment on this forum.   I will need to get more information from you.

For the sack of simplicity here are some of the issues.

1. Location of the access point

2. Detection of the access point IP address and mapping it to a location.

3. Accuracy of the system.  How close does the location system need to represent where the person is.

4. Cost of the system

5. Time to market - Do you have time for research and time to develop the system?

6. How do you monitor the system.

You will need to provide me some more details about the project.  Please look at my contact info on www.pinterec.ca

Chris

Hi

My aim Is actually to build the whole system in an old folks home. This server should be in a room. The old folks will be roaming around in the homes, wearing this watch which will transmit out signel when "critical" limit is achieved.

The system need not show the exact location but at least let the person who is monitoring server, which level and room the signal is transmitted from.

The cost I hope it could be as cheap as possible. I have the time, about couple of months.

I do not know what point 2 mean.

Thanks

Calvin

What I am refer to is that you need to be able to determine which access point is receiving the signal.  If you only have a couple of months to do this task it is likely not a finished product.  I would suggest considering using the area the access point as a zone.  Ofcourse most access points can cover 3 different levels.

I think you biggest problem right now will be a proof of concept and a project plan.   I see a number of wholes in your logic that will need to be looked at .

1. Determine the range of an access point.

2. Create a prototype transmitter and test your system to determine the region of the alarm.

With this you might be able to devleop a low grade non medical system as a demo.

good luck,

Chris Pinter

On the following website you will find a description of a direction finding system. http://www.signal.uu.se/Publications/pdf/c0110.pdf The pattern of the antenna can be changed by steering the parasitic elements. This way the antenna pattern can be rotated electronically. The rotation speed could be between 12 Hz and 2 kHz. Don’t use a frequency that has any relationship with the mains frequency and don’t use a frequency outside the bandwidth of the receiver. The point of maximum signal can be compared with the actual position of the antenna pattern. This way the direction can be determined.  With two such systems at different locations you can find the position of the transmitter. The antennas could be located at the balconies on both sides of the building.

Dear Chris,

I am a pipeline engineer, trying to build what I call "Pipe Radiowave Transmitter and Receivers".  

My test pipeline is 2 inch diameter and 300 m long. About 100 kHz Radiowave signal  from a commercially available RF generator (0.2kHz -2MHz)  is amplified  and aerialed through the pipeline. Receivers are placed at other side. The Transmitter and reciever aerials are install in the pipeline.

Please see if the Block diagram below make sense to you? What comes out as output of the RF is current that are varying at radio frequency. Is this correct?

1. Transmitting antenna (about 100kHz. Must be attached to the RF amplifier)
2. RF signal amplifiers (about 100 watt) compatible with 5
3. Receiving antenna (broad range of frequencies) -compatible with 4
4. RF signal analyser (for the received signal)
5. RF generator (0.2 kHz -2MHz): Spec found: Manufacturer: GW INSTEK, Farnell Order Code: 4911684, Manufacturer Part No: GFG-8015G

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