• FEC Technologies
• Receiver/PHY Technologies
• Waveform Technologies
• Mobile Mesh Networking
• Communication Systems Architecture
• Specialty Processing

TopX Waveform Design Tools

A waveform is defined as the complete signal structure, operation and protocol used by a communication system.  TrellisWare has developed a family of advanced waveforms that we call TopX, for “Topological eXtreme” applications, which enable performance in the harshest RF environments. When built into a waveform design, these technologies can enable:

• mitigating significant signal dynamics due to motion of the users or potential frequency offset degradations in the RF processing
• coherent combining of signal reflections so that multipath may actually improve rather than degrade receive performance
• autonomous mesh relay of signals between users
• frequency diversity and frequency reuse
• minimizing sensitivity to potentially dramatic signal amplitude fluctuations
• mitigating co-channel interference
• extremely robust error correction decoding
• flexibility to adjust to changing signal degradations on the fly
• supporting wide data rate scaling
• optimizing acquisition and tracking to minimize system overhead
• network self-discovery and self-healing
• robust broadcast and multicast in addition to point-to-point communications
• reducing complexity implementations of AID and PSP for enhanced reception processing

TopX Integration Environment

TrellisWare’s TopX waveforms employ the concept of maximally using all the available information globally across an entire communication design. The key concept behind TrellisWare’s waveform architecture is designing interdependencies between each aspect of the waveform, so better performance can be derived in the receive processing.  Most traditional waveform designs have entirely separate groups of people working on each layer of the waveform (802.11, for example, has totally different committees establishing the standards for each layer), which significantly inhibits the possibility of a globally optimum design.

Some communication architectures are more amenable to this waveform approach than others. For example, memory built into the signal structure allows turbo gains in the receive processing, while the lack of memory minimizes the possibility of such gains. Similarly, tightly coupled network and PHY layer designs allow for improved cross-layer design while independently designed network and PHY layers truncate this performance.

In cases where the communication design accommodates this level of design optimization, TrellisWare’s waveform technology allows for dramatic improvements over conventional approaches, often working where nothing else will.

Where TopX Has Been Applied

The choice of modulation and coding, in conjunction with the expected channel and operational constraints, can result in improved performance with reduced complexity of implementation. For instance, our SRW baseband physical layer (PHY) design uses the memory in the modulation in conjunction with the expected multipath environment in such a way that the equalizer/demodulator can be treated as one constituent code, serially concatenated with the convolutional code and processed using turbo decoding techniques.

Several of these technologies are being used in the implementation and enhancement of the SRW waveform. Many are being used in designs for communications in extremely demanding scenarios such as mines, ships and other highly enclosed environments. Other applications of TopX waveform technologies include designs for Low Probability of Intercept (LPI), high throughput enhancements of existing waveforms and space-time coding for MIMO systems.

TopX designed waveforms can also be optimized to provide key PHY layer information for networking use. TrellisWare’s own mesh networking waveforms, for example, are built around a PHY layer design that minimizes the need for network-wide state tables by simplifying the way the information is acquired and relayed.