Technology
Technology
Xtendwave's™ modulation and encoding technology provides existing copper lines with extended broadband rate and reach compared with existing xDSL and cable modem technologies. Xtendwave's™ patented AFBM™ technology is based on proprietary signal processing techniques that enhance the spectrum utilization. Xtendwave's™ wavelet-based technology allows for higher throughput or equivalent rates at farther distances than current xDSL solutions. Additionally, Xtendwave's™ AFBM’s™ integrated test head capabilities, determine the "health" condition of the metallic loop without disrupting traffic. This gives the service provider the ability to prevent service outages and to quickly and effectively locate and solve problems, which decreases the need for truck-rolls or any other types of dispatch.
Regardless of whether the interest is in longer reach or higher throughput, Xtendwave's™ AFBM™ technology helps service providers increase revenues by making it possible to bring broadband services to customers that were previously unreachable due to the limitations of the existing technology. Xtendwave's™ AFBM™ technology also helps reduce operating and maintenance costs by delivering integrated testing of the copper pair.
Understanding AFBM™ Technology
Transmission and Time-Frequency Localization of Symbols
Encoding and modulation comprises the selection of a set of base-band symbols with the assignment or mapping of data elements, and, therefore, allocation of energy to these symbols. Symbols, in turn, comprise frequency components having finite energy levels, which exist for some time duration.
Intuitively, given a finite quantity of energy to allocate to frequency components, a symbol that is more compact in both frequency and time provides a better utilization of bandwidth than one that is less so. In addition, a symbol that has shorter time duration is less susceptible to interference with other symbols that are transmitted consecutively. And, finally, assigning transmitter energy to a more compact representation in time and frequency yields a symbol that is less degraded by noise.
Since there is a fundamental limitation on the concurrent "compaction" of a symbol's time duration and its frequency content the selection of symbols for data encoding is of importantance for optimization and performance.
Xtendwave™ believes the generation of symbols and assignment of transmitter power spectral density by wavelet filter banks to be the best solution to this problem. Conceptually, AFBM™ represents base-band symbols as coordinates in wavelet space. AFBM™ wavelet space is spanned by special wavelets that are spectrally adapted to the channel.
Results
Xtendwave's™ AFBM™ technology results in a transmitter and receiver design that produces and acquires signals with better spectral efficiency, temporal efficiency and noise immunity, than those obtained with Discrete Multi-Tone (DMT) techniques. As a result, the AFBM™ signal has higher bits per second per Hertz at a given BER than DMT.
Figure 2
Figure 2 shows the BER to SNR curves comparing DMT with Xtendwave's™ AFBM™ technology for equal spectral efficiencies of approximately 1.7b/s/Hz. Xtendwave's™ AFBM™ technology is almost two orders of magnitude better than DMT at a SNR of 6 dB, and almost three orders of magnitude better than DMT at an SNR of 10 dB.
IP Patents
Xtendwave™ owns the intellectual property and patents to bring its AFBM™ technology to market.
Issued
- Code division multiple access employing orthogonal filter banks
- Patent #: 7,394,844
- Inversion of channel distortion by adaptive wavelet lifting
- Patent #: 7,362,816
- Optimal filter-bank wavelet modulation
- Patent #: 7,333,665
- Transmission of encrypted messages between a transmitter and a receiver utilizing a one-time cryptographic pad
- Patent #: 7,327,845