Wireless Communications/rf..


what type of filter do you need using 2 different devices on the same 2 ghz frequencies

If two wireless devices are using the same radio frequency spectrum you can not separate them with a frequency selective filter.  There are other possibilities to keep their transmissions separate, though:
If the systems are pulsed or 'part time' they can be time synchronized.   This is the system used in TDMA (time division multiple access) systems.   A system controller sets up time 'slots' and assigns those slots to different users.  Every user can be using the same radio spectrum but at different times.  
Another approach is to use spread spectrum techniques, such as CDMA (code division multiple access) where the systems encode their information streams with a digital sequence that increases the bandwidth, but in a way that the receiver can decode just that signal even though other users are transmitting, at the same time, but with a different spreading sequence.  

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Jerry Hinshaw


RF and microwave engineering, hardware and systems applications. Avionics, satellite, and terrestrial communications. Space communications and navigation, geo-location services via satellite and ground-based wireless systems. Systems integration of RF and wireless services. Electric Utility RF Smart Meter (SmartMeter) and Smart Grid wireless devices and networks. Utility Distribution Automation.


30 years experience in microwave and RF systems engineering, radio hardware design and development.

about 20 articles, 2 patents

BSEE MSEE Communications Systems

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