Air Interface Design by Transmitter Orientation and Receiver Orientation
Conventional transmission schemes are transmitter oriented, which means that the transmitter algorithms are a priori given, whereas the algorithms to be used at the receivers have to be a posteriori adapted under consideration of channel state information. In contrast to transmitter orientation, in receiver oriented systems the receiver algorithms are a priori given, and the transmitter algorithms, again under consideration of channel state information, have to be a posteriori adapted correspondingly. Recently, receiver oriented schemes have been proposed as promising approaches for mobile radio downlinks which utilize the duplexing scheme TDD. In such applications the rationale receiver orientation may offer the following advantages:
The a priori determined receiver algorithms can be chosen with a view to arrive at particularly simple receiver structures. In this way, as compared to transmitter oriented systems, complexity can be transferred from the MTs to the AP.
Channel information is only required at the AP. Therefore, no downlink transmission resources have to be sacrificed for training signals, and no channel estimators are required at the MTs.
The project has the focus to illuminate the basic commonalities and differences between the two rationales transmitter orientation and receiver orientation. Based on the gained results proposals for future air interfaces should be developed.