LTE: Is DC carrier numbered for downlink?

Question

With Cross Carrier Scheduling, UE do not ned to read pdcch on secondary cell.

Can here we assume that such secondary cells does not transmit PDCCH channel and only transmit reference channel, MIB and PDSCH?

Answer 1

You have asked DC carrier has any number as resource element?

DC stands for Direct Current and it travels unmodulated. it is a subcarrier that has no information sent on it. This is an important subcarrier in OFDM based systems. It is used by the mobile device to locate the center of the OFDM frequency band. So if LTE does not have a DC subcarrier, it would be a big deal.

For pictorial representation you can look at figure 5.4.2-1 of 36.101 V8.3.0

Yes it's not been numbered or assigned any resource element.

Consider 20 MHz channel bandwidth with 1200 used carriers. On resource element rather we would see carrier 0, 1, 2,... 599 adjacent to DC from the left, then DC without number skipped, 600, adjacent to DC from the right, 601...and so on. Or, in other words, mapping formulas never fall onto DC carrier, as it has no number in resource element grid.