Equal power output spatial spreading matrix for use in a wireless MIMO communication system

A method of wirelessly transmitting data via a plurality of transmission antennas, the method comprising:

• encoding the data to produce two or more encoded spatial data streams, wherein a number, NSS, of the encoded spatial data streams is less than a number, NTX, of the transmission antennas to be used to transmit the encoded spatial data streams;
• and
• utilizing a spatial spreading matrix Q to distribute the two or more encoded spatial data streams to the transmission antennas,
• wherein:
• Q has NTX, rows and NSS, columns,
• Q satisfies one or more of the following two constraints:
• 
• ∑
• l
• =
• 1
• N
• SS
• ⁢
• Q
• ⁡
• (
• t
• ,
• l
• )
• 
• 2
• =
• A
• t
• ⁢
• B
• (
• a
• )
• for all t=1 . . . NTX, or
• 
• ∑
• l
• =
• 1
• N
• SS
• ⁢
• S
• l
• ⁢
• Q
• ⁡
• (
• t
• ,
• l
• )
• 
• 2
• =
• A
• t
• ⁢
• B
• (
• b
• )
• for all t=1 . . . NTX when Sl is equal to (i) 1 or (ii)−1,
• Q(t,l) is a component of Q at row t, column l,
• Sl is a symbol in an 1-th spatial stream,
• B is a constant, and
• A1, A2, . . . , ANTX is a sequence of constants designed, when at least some power amplifiers corresponding to the NTX transmission antennas have different operating regions, based on the linear operating regions of the power amplifiers.