Differential space-time modulation (DSTM) for multiple antenna communication systems has been recently proposed for frequency-nonselective fading channels. In broadband multirate systems, frequency-selective fading may occur. In this paper, the DSTM in frequency-selective fading channels is considered. A linear equalizer for the DSTM is proposed over frequency-selective fading channels. Further...

In this paper we have studied channel models (flat fading and frequency selective fading channels) estimation, adaptive equalization, and demodulation. The technique involves the optimization of the overall impulse response of the transmit and receive filters and effectively reduces the channel to one which is flat fading. This example showed the relative performance of linear and decision feed...

abstract the study aimed at investigating the efficacy of written corrective feedback (cf) in improving iranian efl learners’ grammatical accuracy. it compared the effects of focused and unfocused written cf on the learners’ grammatical accuracy. 75 efl students formed a one control and two experimental groups. the focused feedback group was provided with error correction in tenses. the unfocus...

Selective suppression of transmission at feedback synapses during learning is proposed as a mechanism for combining associative feedback with self-organization of feedforward synapses. Experimental data demonstrates cholinergic suppression of synaptic transmission in layer I (feedback synapses), and a lack of suppression in layer IV (feedforward synapses). A network with this feature uses local...

We examined function of the feedback pathway from A17 GABAergic amacrine cells to rod bipolar cells (A17 feedback), a critically located inhibitory circuit in the classic rod pathway of the mammalian retina whose role in processing of scotopic visual information is still poorly understood. We show evidence that this A17 feedback has a profound influence on the temporal properties of rod-driven ...

We propose a novel wearable haptic device that can provide kinesthetic feedback for stiffness rendering of virtual objects in augmented reality (AR). Rendering using is crucial realistic finger-based object manipulation, yet challenging particularly AR due to the co-presence real hand, device, and rendered scenes. By adopting passive actuation with tendon-based transmission mechanism, proposed ...

Primate posterior parietal cortex (PPC) is known to be involved in controlling spatial attention. Neurons in one part of the PPC, the lateral intraparietal area (LIP), show enhanced responses to objects at attended locations. Although many are selective for object features, such as the orientation of a visual stimulus, it is not clear how LIP circuits integrate feature-selective information whe...