Method and Apparatus for Determining a Precoding Matrix for Precoding Symbols to be Transmitted to a Plurality of Wireless Devices

European Patents EP2518906A1 and EP2518906B1, Brazilian Patent BR112013009453A2, Canadian Patent CA2816387A1, Chinese Patent CN103201961A, Spanish Patent ES2444119T3, Japanese Patents JP2013531931A and JP5277361B2, Korean Patent KR20130097783A, Mexican Patent MX2013004645A, Polish Patent PL2518906T3, Russian Patent RU2013117279A, US Patents US2013279628A1 and US8693574B2, WO2012146739A1p