We propose an efficient collusion-attack-resistant position-verification protocol in a new model named multi-channel model. In the multi-channel model, there are lots of communication channels. When a player picks a random channel and sends a short message over it, the message might slip by an adversary with high probability if the adversary does not know the channel beforehand. This idea is mo...

Multi-channel acoustic echo cancellation is basically composed of two parts. One part is a multi-channel system identification problem which is nontrivial to solve. The other part, which is also nontrivial, is the so-called double-talk detection problem. Nearend speech detection is based on a test statistic. Recently, a new double-talk test statistic based on the normalized cross-correlation ve...

We have developed a wideband receiver system for simultaneous observations in CO lines of J = 2-1 and 3-2 transitions using the Osaka 1.85-m mm-submm telescope. As frequency separation system, we multiplexers that connect three types diplexers, each consisting branch-line couplers high-pass filters. The radio (RF) signal is eventually distributed into four bands, which fed to superconductor-ins...

Multi-radio multi-channel multi-hop wireless networks have recently received a substantial amount of interest. An important question in multi-radio multi-channel networks is how to perform efficient network-wide broadcast. However, currently almost all broadcasting protocols assume a single-radio single-channel network model. Simply using them in multi-channel environment without careful enhanc...

In this paper, we present a routing and channel assignment protocol for multi-channel multi-hop wireless networks. We consider a multi-hop network, where a mobile host may connect to an access point using multi-hop wireless routes, via other mobile hosts or wireless routers. Also, we consider a multi-channel network where multiple non-overlapping (orthogonal) channels are available, and each ho...