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I need to find the emission power of a WiFi mobile phone antenna. I have checked the IEEE 802.11 specifications but it says that the power transmission is variable and depends on the mobile phone fabricant and power saving options.

I also searched for information about some specific mobile phones but the datasheets available on the Internet seem quite weak and do not say anything about WiFi power transmission.

Is there a complete datasheet of mobile phones? How can I determine the transmission power in the WiFi antenna of a specific mobile phone?

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  • $\begingroup$ The best way is to look at the protocol specifications. It is highly unlikely the mobile phone manufactures will publish this data. For example look at the 802.11 specifications you are almost certain to find this infomation. I suggest that you include more infomation as the engineering problem you are trying to solve, and you have a better chance of getting a good response. As it is this question will be closed as a poor question. $\endgroup$ – Mahendra Gunawardena Jun 15 '15 at 1:50
  • $\begingroup$ Thanks for revising the question. I've gone even farther with an edit that demonstrates how to ask your question in a way that fits our guidelines. In this form, the question might be answered more productively. $\endgroup$ – Air Jun 15 '15 at 17:33
  • $\begingroup$ @MahendraGunawardena, It is just what I was looking for. Giving some examples of Wifi modules was the key. And of course, the FCC search form. Thank you! $\endgroup$ – agonza1 Jun 18 '15 at 14:51
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Not too sure if you will be able to find datasheet for specific cell phone. These are proprietary information and mobile phone manufactures usually don’t share this type of information in public for various reasons. Depending on the business needs you should contact the vendors directly and seek datasheet, which might be obtained under a non-disclosure agreement (NDA). But there are a couple of other ways that you can obtain similar data.


Access Public Data from Federal Communications Commission (FCC)
If the mobile phone is sold in USA, then the mobile phone manufacture has to file a report with the FCC. This is public information, thus accessible through FCC web site. These reports will give you transmission power levels per the FCC test criteria, which might not be exactly what you are seeking, but you will get close. You will need the FCCID for the particular mobile phone which you should be able to find. Below is output power specification for a Samsung Galaxy S4.

Samsung Galaxy S4
IEEE 802.11 output power levels for Samsung Galaxy S4 (FCC)

FCCID Search form is a good place to start. You might be able obtain similar infomation for European Union (EU) too.


Test using Semi-anechoic chambers
This might be tedious and expensive, but can be done. There are a plethora of EMC test facilities that will glad to help you get this data.


Test using a GTEM chamber
This is less expensive, and can be done much more easily as long as you have access to the chamber and spectrum analyzer.

GTEM Chamber with Spectrum Analyzer


Specification from Wifi Module
But you might want to review widely available wifi modules. This might be the most practical method because you have access to datasheets with tolerances etc. Here are a few examples:

enter image description here

Chances are a wifi module with similar transmission power capabilities are in mobile phones.


References:

  1. Federal Communications Commission USA
  2. FCC ID Help
  3. Samsung Galaxy S4 FCC Report
  4. 20 Highest and Lowest Radiation Cell Phones
  5. FCC Wireless Phones FAQS
  6. PCTEST Engineering Laboratory Inc
  7. Is interference between aircraft an issue for fly-by-wireless technology?
  8. License-Exempt Wireless Applications for Public Safety
  9. How to find out which certificates (FCC, CE etc.) are necessary for a product?
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  • $\begingroup$ I have been checking my mobile phones and I noticed that I also have FCCID and those devices were bought oustide USA. Is it possible that those devices have to pass the FCC test as well? $\endgroup$ – agonza1 Jun 18 '15 at 17:33
  • $\begingroup$ @Alb, this might be another good question for the forum. The design as been approved, it doesn't mean that devices purchased with the same FCCID has passed the test. It is the responsibility of manufacture ensure all devices meet FCC guidelines $\endgroup$ – Mahendra Gunawardena Jun 18 '15 at 22:36
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Typically, the max is 100mW (20dBm). You can refer to an example wifi chip datasheet (This one is used in many mobile phones with Snapdragon processor) - https://developer.qualcomm.com/download/sd410/wcn3620-wireless-connectivity-ic-device-specification.pdf

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There is a list of some widely used devices and their transmit power (and many other properties) in an easily digestible table: https://clients.mikealbano.com/ The most smartphones seem to be just around 20 dBm and the maximum lies around 30 dBm.

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