Section: 6.10.3A Demodulation reference signals associated with EPDCCH, MPDCCH, or SPDCCH
Content: The demodulation reference signal associated with EPDCCH/MPDCCH/SPDCCH - is transmitted on the same antenna port as the associated EPDCCH/MPDCCH/SPDCCH physical resource; - is present and is a valid reference for EPDCCH/MPDCCH/SPDCCH demodulation only if the EPDCCH/MPDCCH/SPDCCH transmission is associated with the corresponding antenna port; - is transmitted only on the physical resource blocks upon which the corresponding EPDCCH/MPDCCH/SPDCCH is mapped. A demodulation reference signal associated with EPDCCH/MPDCCH/SPDCCH is not transmitted in resource elements in which one of the physical channels or physical signals other than the demodulation reference signals defined in 6.1 are transmitted using resource elements with the same index pair regardless of their antenna port .