最新的211协议里给出了很多种天线端口,有CRS,和PDSCH相关的DMRS,和PDCCH相关的DMRS,还有定位参考信号PRS的端口,以及CSI参考信号的天线端口,在最开始也说明了天线端口的意思即:
An antenna port is defined such that the channel over which a symbol on the antenna port is conveyed can be inferred from the channel over which another symbol on the same antenna port is conveyed. There is one resource grid per antenna port. The set of antenna ports supported depends on the reference signal configuration in the cell:
- Cell-specific reference signals support a configuration of one, two, or four antenna ports and are transmitted on antenna ports p=0 ,p={0,1} , and p={0,1,2,4} , respectively.
- MBSFN reference signals are transmitted on antenna port p=4.
- UE-specific reference signals associated with PDSCH are transmitted on antenna port(s) p=5,p=7,p=8 , , or one or several of p={7-14} .
- Demodulation reference signals associated with EPDCCH are transmitted on one or several of p={107-110}.
- Positioning reference signals are transmitted on antenna port p=6.
- CSI reference signals support a configuration of one, two, four or eight antenna ports and are transmitted on antenna ports p=15 , p=15,p=16 , p=15-18 and p=15-22 , respectively.
Two antenna ports are said to be quasi co-located if the large-scale properties of the channel over which a symbol on one antenna port is conveyed can be inferred from the channel over which a symbol on the other antenna port is conveyed. The large-scale properties include one or more of delay spread, Doppler spread, Doppler shift, average gain, and average delay.