The spat between Wi-Fi MIMO specialist Ruckus and Wi-Fi router maker Netgear seems to come down to simple economics. Ruckus is suing Netgear, along with its new MIMO antenna supplier Rayspan, for patent infringement, over the antenna designs and associated software that have replaced the Beamflex technology which Netgear used to buy from Ruckus. The suit was brought in the US Court for the Northern District of California last week. The two patents specifically refer to antenna designs using multiple selectable horizontal and vertical elements, and the RF circuit board to which they are connected. Rayspan was founded in 2006, to build air interfaces using what it calls ‘metamaterials’, which enable ultra-compact MIMO antennas. It says that its antennas work…