# Should we use Maximal ratio combining and an equalizer together?

I have confusion on MRC (Maximal Ratio Combining) method, which I would like to clarify. An example is where I have 1 transmit antenna and 4 receive antennas. The concept of MRC is to combine all the signals from the 4 receive antennas such that the combined SNR is increased (given the phase is corrected). To achieve this, a weight is computed for each antenna branch, such that it weights the received signal in proportion to the signal strength.

Once the MRC process is completed, are we required to equalize the channel effect with some equalizer (for e.g. ZF or MMSE). Most of the online materials refer to MRC as a equalizer, which is causing confusion. With my understanding, we should equalize, as the MRC is only increasing the SNR but not inversing the channel effect.

If we require to use an equalizer (ZF / MMSE) after combining, which channel coefficient should we use? Because once the received symbols are combined, we just have a vector (with increased SNR). But the channel coefficients are different between 1 tx antenna and each 4 rx antenna.