Vanu (United States)

Two time-invariant rateless code constructions are developed for efficient communication over multi-input multi- output (MIMO) Gaussian channels. Both architectures employ layering, dithering, and repetition as key ingredients, and convert the MIMO channel into a scalar channel to which classical Gaussian base codes can be applied. Both constructions are convolutionally structured - one is based on faster-than-Nyquist (ftN) signaling, while the other on a diagonal layering (DL) structure. Moreover, both employ successive cancellation decoding. We show that ftN rateless codes are asymptotically capacity achieving at any signal-to-noise ratio (SNR) and induce a time-invariant scalar channel. We also show that DL codes are capacity achieving at any SNR, and induce a particular time-varying scalar channel to which standard LDPC base codes can be applied without significantly sacrificing performance.

The Anywave Network-In-a-Box cellular system has been used by military customers to integrate commercial cellular communications into their existing telephone networks. The combination of flexible software with COTS hardware provides a low-cost solution that supports a wide variety of network interfaces. This paper describes the integration of a Network-In-a-Box system into two different military telephone networks, and discusses some of the design and integration challenges faced. A key component of the integrated solution is the Asterisk open-source PBX application. The first case study shows how Asterisk can be easily used to connect the VoIP-based Network-In-a-Box system to a legacy T1 telephone network. The second case study describes how the standard Network-In-a-Box was enhanced with Type 1 secure communication capabilities in order to interconnect a GSM cellular network with a classified VoIP network.

In the above titled paper (ibid., vol. 49. no.9, pp. 2309-2313, Sep 03), several equations were printed incorrectly. The corrections are presented.