It is well known that the capacity region of an average transmit power constrained Gaussian Broadcast Channel (GBC) with independent noise realizations at receivers enlarged by presence causal noiseless feedback. When variances are identical, even passive feedback via memoryless links can lead to a enlargement. The last fact remains true when variance very high, and available only from one rece...

This study used questionnaires eliciting quantitative and qualitative data to investigate (1) foreign language learners’ beliefs about peer feedback on pronunciation before after a intervention (2) providers’, receivers’, teacher receivers’ experiences of the intervention. Participants included 127 first-year learners German. They were assigned provider group, receiver or control group. After g...

Some type of transmission rate control protocol is required in order to support multicast video applications over the Internet. Previously, we proposed a new protocol, the Layered Multicast Control Protocol (LMCP), which utilizes both the video sender and the receivers to control the rate of the video transmission. One weakness of this approach is that feedback from all receivers is required in...

ATELLITE networks will have a crucial role for global s multicast services due to their large coverage area, abundant bandwidth particularly at higher frequency, and rapid network setup. As in terrestrial reliable multicasting cases, however, feedback implosion 141, [6], [9] is identified as a major problem in satellite multicast. The feedback implosion occurs when a large number of receivers s...

Some type of transmission rate control protocol is required in order to support multicast video applications over the Internet. Previously, researchers have proposed two basic families of control protocols. The first, sender based rate-adaptation, focuses on the sender. The sender uses a single channel to transmit the video signal to all receivers, and the sender adjusts the transmission rate o...

Real-time media streams that use RTP are, to some degree, resilient against packet losses. Receivers may use the base mechanisms of the Real-time Transport Control Protocol (RTCP) to report packet reception statistics and thus allow a sender to adapt its transmission behavior in the mid-term. This is the sole means for feedback and feedback-based error repair (besides a few codecspecific mechan...

Real-time media streams that use RTP are, to some degree, resilient against packet losses. Receivers may use the base mechanisms of the Real-time Transport Control Protocol (RTCP) to report packet reception statistics and thus allow a sender to adapt its transmission behavior in the mid-term. This is the sole means for feedback and feedback-based error repair (besides a few codecspecific mechan...

In this paper, we describe and evaluate a mechanism for ltering RTCP receiver reports sent from receivers to the whole session. In large multi-cast groups, such feedbacks could induce network congestion, receivers overload and feedback delay. The proposed ltering mechanism provides a clas-siication of receivers according to a predeened similarity measure (e.g. packet loss rate observed or TCP-f...

Various Internet applications involve multiple parties and usually adopt a one-to-many communication paradigm (multicast). The presence of multiple receivers in a multicast session rises the problem of inter-receiver fairness. Transmitting with a rate which matches the slowest receiver will limit the throughput of other receivers and thus their satisfaction. A multi-rate mechanism where the rec...

This study analyzes the impact of transmitter noise on the performance of multiple-input multiple-output (MIMO) systems with linear and nonlinear receivers and precoders. We show that the performance of MIMO linear and decision-feedback receivers is not significantly influenced by the presence of transmitter noise, which does not hold true in the case of MIMO systems with precoding. Nevertheles...