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If you use an actual SoC such as the Qualcomm Snapdragon Processor for mobile communications would it be possible to have two cores both sharing a common IO (Cellular/WiFi/GPS/Bluetooth) integrated circuits but its own separate antenna ?

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I believe that's default. All cores share resources (IO being one of them). Each of the cores wouldn't have their own antenna though, no. Wifi/Cell/GPS/Bluetooth may have their own antenna though. There's no point in duplicate antenna for two different applications because one would cause so much noise on the other one that you'd never be able to receive anything besides what the other antenna is broadcasting.

Instead, the standard way to do multiple things on an antenna is to do TDM (Time division multiplexing).

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  • \$\begingroup\$ Hello hota and Simon. Thank you both for the responses. Horta one question to ask. Is it possible even in just theory to have two antennas one for one core and another antenna for a secondary core ? Does the location of the core on die play a factor ? So if one of the cores is located somewhere other than on the top most layer can a baseband processor and lna, modulator oscillator and amplifier be embedded on this layer ? \$\endgroup\$
    – VictorM
    Dec 14 '15 at 4:42
  • \$\begingroup\$ @VictorM As I stated in the answer, if you have another broadcasting antenna working in the same frequency range, the two will clobber each other. From any sort of distance from the device, the receiver will see two sinusoidal waves added together. At the worst, a phase offset of 180 degrees will result in absolutely nothing being seen at the receiver because the two antenna just cancelled each other out. Can I ask what your application is and why TDM won't work for you? \$\endgroup\$
    – horta
    Dec 14 '15 at 12:05
  • \$\begingroup\$ @VictorM Even if you have them in phase with 0 degree offset, they'll be adding together and if one sends a 0 and the other sends a 1, the receiver won't be able to tell which antenna sent the 0 and which sent the 1. \$\endgroup\$
    – horta
    Dec 14 '15 at 14:02
  • \$\begingroup\$ Thank you @Horta for the above response. Would you please use your expertise describe whether two antennas could exist if the frequencies ranges used by each antenna are not of the same range ? Would it be possible to embed the second transceiver IC (baseband IC) on a separate layer other than where the primary transceiver IC (baseband processor) is located on die ? Many thanks. \$\endgroup\$
    – VictorM
    Dec 15 '15 at 6:57
  • \$\begingroup\$ Thank you again @Horta. With respect to the last question you had asked about the application. What I can tell you is that the details which I am asking is for strictly research and hypothetical purposes. At the moment there is no plans for any such a design. I wish I could reply with regards to the TDM term you have used above but I am in process of understanding what exactly this term applies to and its meaning for a layman like myself. \$\endgroup\$
    – VictorM
    Dec 15 '15 at 7:15
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RF protocols using the same frequency will interfere heavily, regardless of the number of antennas, so the best thing you can do is implement them in the same place and try to coordinate the services, for example by delaying outgoing Bluetooth frames while a WiFi packet is being received, because starting a transmission would interrupt the active transfer, and probably not manage to send out a packet undisturbed.

For protocols on different frequencies, you can use analog bandpass filters to isolate the different transceivers. Whether you use the same, or different antennas does not matter that much then -- the antenna geometry must match any frequency range you plan to use.

In order to reach different frequency bands at the same time, you need multiple transceivers anyway -- while it is possible to build a wideband transceiver, this is ridiculously expensive and gives worse performance, so it is uninteresting both from an economic and an engineering point of view.

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