The Turbo Principle in Sustainable and Developmental Learning Design

This chapter conveys two key success strategies for complex, self-guided interdisciplinary learning: (1) rhythmizing as a theatrical tool (regarding organization along time) and (2) multi-perspectivism as a tool allowing the organization regarding viewpoints (in the space of perceptions). While the first can be achieved by a suitable script of the didactic process, the second can be supported by seating orders, the arrangement of tables, and allocation of roles to role-playing learners. The meaning of “roles” in game-based learning is analyzed, based on both literature and interdisciplinary teaching experience. As an example of role-based and game-based learning, this chapter analyzes the temporal dynamics of several social dimensions of learning in the case of the five-level negotiation game “Surfing Global Change” (SGC, © G. Ahamer).

Forward and backward RLS-DDCE processing in MIMO-OFDM spatial multiplexing receivers

In this paper we present a novel approach in frequency domain channel estimation technique. Our proposal is based on the recursive least squares (RLS) algorithm combined with the decision making process called decision directed channel estimation (RLS-DDCE). The novelty and key concept of this technique is the block-wise causal and anti-causal RLS processing that yields two independent processing of RLS along with the associated decisions. Due to the implemented low density parity check (LDPC) code the receiver operates with soft information, which enables us to introduce a new modification of the Turbo principle as well as simple addition of the a-posteriori log-likelihood ratios (LLRs). Although the computational complexity is increased by both of our approaches, the latter is relatively less complex than the earlier. Simulation results show that these implementations outperform the simple RLS-DDCE algorithm and yield lower bit error rates (BER) and more accurate channel information.