Efficient Joint Estimation and Compensation of CFO, Tx/Rx Frequency-Selective I/Q Imbalance, and the MIMO Radio Channel in OFDM Systems

Table 5

Computational complexity expressions for the actual compensation.

Approach	Number of real MULs (per data symbol)
Joint Tx IQ + Ch., R	(6+𝐿c)𝑁𝑅(𝑁CP+𝑁)𝑁𝐷+8𝑁𝑇𝑁𝑅
Joint Tx IQ + Ch., C	(5+4𝐿c)𝑁𝑅(𝑁CP+𝑁)𝑁𝐷+8𝑁𝑇𝑁𝑅
Sep. Tx IQ + Ch., R	𝜅𝑁𝑅((6+𝐿c)𝑁CP+4𝑁𝐷(𝜅𝑁𝑅+𝑛𝑠)+(6+𝐿c)𝑁)𝑁𝐷𝑛𝑠
Sep. Tx IQ + Ch., C	𝜅𝑁𝑅((5+4𝐿c)𝑁CP+4𝑁𝐷(𝜅𝑁𝑅+𝑛𝑠)+(5+4𝐿c)𝑁)𝑁𝐷𝑛𝑠