求助一下 谁能解释下ePDCCH?

enhanced downlink control channel；
to improve capacity, frequency interference;
consisted of ecce/ereg;
concept created of epdcch set with distributed or localised type;
same coding(but without multiplexing with all cell ues such as pdcch) and modulation(qpsk) scheme as pdcch ;
located in pdsch region with flexible resource allocation;
etc..

个人理解，用PDSCH的方式来发送DCI。