Given: You are evaluating the theoretical and real-world RF gain benefits of transmit and receive features
introduced by 802.11n with MIMO. This exercise allows you to quantify the feature’s value in a real-world
environment.
What is the maximum theoretical signal gain of chip-based TxBF and MRC (as features) when compared tothe same AP using only a single antenna for transmit and receive (effectively simulating a 1×1 chip)?

A.
2 Rx or Tx chains = 3 dBi gain
3 Rx or Tx chains = approx 5 dBi gain
4 Rx or Tx chains = 6 dBi gain

B.
2 Rx or Tx chains = 1 dBi gain
3 Rx or Tx chains = 2 dBi gain
4 Rx or Tx chains = 3 dBi gain

C.
2 Rx or Tx chains = 3 dBi gain
3 Rx or Tx chains = 6 dBi gain
4 Rx or Tx chains = 9 dBi gain

D.
2 Rx or Tx chains = approx 4-6.5 dBi gain
3 Rx or Tx chains = approx 7-10 dBi gain
4 Rx or Tx chains = approx 10-12 dBi gain

E.
The theoretical gains offered by each additional radio are different for TxBF and MRC.