The article "Massive MIMO: Ten Myths and One Critical Question" by Emil Björnson, Erik G. Larsson, and Thomas L. Marzetta addresses common misconceptions about Massive MIMO (multiple-input multiple-output) technology and its practical applications. Despite its potential to handle orders of magnitude more data traffic, Massive MIMO is often misunderstood due to several widespread myths. The authors debunk ten common myths, including the notion that Massive MIMO is only suitable for millimeter-wave bands, requires an order of magnitude more antennas than users, and necessitates high-precision hardware. They also highlight that Massive MIMO can achieve significant performance gains through linear processing and that resource allocation and power control are simplified in Massive MIMO systems. The critical question posed is whether Massive MIMO can work in frequency-division duplex (FDD) operation, which is crucial for its broader adoption. The article concludes by emphasizing the need for further research to determine if Massive MIMO can be adapted to FDD, particularly in terms of channel estimation and overhead signaling.The article "Massive MIMO: Ten Myths and One Critical Question" by Emil Björnson, Erik G. Larsson, and Thomas L. Marzetta addresses common misconceptions about Massive MIMO (multiple-input multiple-output) technology and its practical applications. Despite its potential to handle orders of magnitude more data traffic, Massive MIMO is often misunderstood due to several widespread myths. The authors debunk ten common myths, including the notion that Massive MIMO is only suitable for millimeter-wave bands, requires an order of magnitude more antennas than users, and necessitates high-precision hardware. They also highlight that Massive MIMO can achieve significant performance gains through linear processing and that resource allocation and power control are simplified in Massive MIMO systems. The critical question posed is whether Massive MIMO can work in frequency-division duplex (FDD) operation, which is crucial for its broader adoption. The article concludes by emphasizing the need for further research to determine if Massive MIMO can be adapted to FDD, particularly in terms of channel estimation and overhead signaling.