Charles E. Rohrs

Learn More
Theory and experiments show that as the per-flow product of bandwidth and latency increases, TCP becomes inefficient and prone to instability, regardless of the queuing scheme. This failing becomes increasingly important as the Internet evolves to incorporate very high-bandwidth optical links and more large-delay satellite links.To address this problem, we(More)
Abstract— We consider dynamic routing and power allocation for a wireless network with time varying channels. The network consists of power constrained nodes which transmit over wireless links with adaptive transmission rates. Packets randomly enter the system at each node and wait in output queues to be transmitted through the network to their(More)
The Digital Signal Processing Group develops signal processing algorithms that span a wide variety of application areas including speech and image processing, sensor networks, communications, radar and sonar. Our primary focus is on algorithm development in general, with the applications serving as motivating contexts. Our approach to new algorithms(More)
We consider power and server allocation in a multibeam satellite downlink which transmits data to <i>N</i> different ground locations over <i>N</i> time-varying channels. Packets destined for each ground location are stored in separate queues and the server rate for each queue <i>i</i> depends on the power <i>p<sub>i</sub></i> (<i>t</i>) allocated to that(More)
We consider power and server allocation in a multibeam satellite downlink which transmits data to N different ground locations over N time-varying channels. Packets destined for each ground location are stored in separate queues, and the server rate for each queue i depends on the power pi(t) allocated to that server and the channel state ci(t) according to(More)
Wireless vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication holds great promise for significantly reducing the human and financial costs of vehicle collisions. A common characteristic of this communication is the broadcast of a device's core state information at regular intervals (e.g. a vehicle's speed and location, or a traffic(More)
We study the provision of deterministic rate guarantees over single crossbar switches. Birkhoff decomposition yields a general approach for this problem, but the required complexity can be very high and the quality of service can be unsatisfactory for practical traffic sources. We develop a method called rate quantization which works with any resource(More)