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SIMO vs Antenna Diversity


I wanted to know if SIMO (Single Input Multiple Output) and Antenna Diversity are the same.

I read that antenna Diversity can eleminate multipath distortions since it has two or more receiver Antennas. Antenna Diversity uses single transmitting antenna.

SIMO also uses Single transmitting antenna and two or more reciever Antennas and eleminates multipath distortions.

Ae both the same? Can you explain to me the differences?

New Member

Re: SIMO vs Antenna Diversity


The more i read on this...the more questions in my mind..... :) Pl help solve them.

1. Is Antenna Diversity similar to SIMO or MISO ?

2. I read on the net that SIMO = Reciver Diversity and MISO = transmitter Diversity? Is this true?

3. When we say Antenna Diversity and i have a total of two Antennas on my device? then in antenna Diversity..Are both Used for Tx and Rx (then it would be MIMO rite)or

is it that Antenna Diversity uses a single transmitting antenna and Multiple Receiving antenna? i read one article on the net.

4. I guessed this may be bec while transmitting, the radio will choose only one of the two antennas and while receiving, the radio hardware listens to the begining of the incoming transmission (the preamble stuff) and compares the signal strength on both antennas. It then selects the stronger antenna (best SNR) and receives the body of the packet on that antenna and this is processed by the Radio chip. Is my assumption correct?

5. So is Antenna Diversity and SIMO the same? Or Is it that two antennas are used for Transmit also? iam confused about explain.

6. I also read that in the diversity system, only one of the two antennas is active (transmit or receive) at any given is this selected?

is it priority driven(which one has higher priority) or time shared?

7. One last question... In Antenna Diverity, one radio has two or more Antennas and it detects and switches to to whichever antenna has a better Signal(best SNR). Does the same happen in MIMO? Or is it neccessary to have two radio chips for simulataneous transfer from both the antennas?

Looking forward for your replies.

New Member

Re: SIMO vs Antenna Diversity

Can anyone throw some light here!!

SIMO vs Antenna Diversity

Antenna Diversity, is an antenna technique to use multiple antennas to improve quality and reliability of a wireless link. You dont equate SIMO, MISO, MIMO to antenna diversity. Those are type of antenna configuration that uses Antenna Diversity.

A good explanation of Antenna Diversity can be read from Wikipedia, you can have different type of antenna schemes. Like you mentioned SIMO and MISO can be a Transmit/Receive Diversity (it doesn't mean it's Transmitter-Receiver Diversity), the SIMO and MISO you mentioned can also be using Spatial Diversity or Polarization Diversity (it really depends on the Antenna system your wireless equipment has).

You antenna system can use different processing techniques to achieve diversity, such as switching, selecting, combining, dynamic control, etc.

I am confident your question is more on the processing techniques of Antenna Diversity, read on there's a lot to learn...

Bottom line is antenna system like SIMO, MISO, MIMO can use Antenna Diversity (SISO can't or I might be wrong, I am not sure)

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