Applied Technology Institute (ATI Courses) offers High-Level Wireless Digital Communications for Program and Engineering Managers course.
This added material discusses the needs to develop a cognitive system in order to mitigate the effects that the environment has on communications and/or data links. Cognition is the ability for system/systems to monitor, record, sample, test, and to be cognitive or aware of the surrounding environments; and then adapts, modifies, or changes the system to improve the Quality of Service.
The basic concept is developing a system, radio, antenna, in a network, and using the available resources to monitor the environment and make an optimal change to the system to improve the Quality of Service QoS of the wireless link.
There are many changing factors of the environment that requires a system to be cognitive and adapt to these changes to mitigate their effects on the communications/data link system. These include jammers both friendly and unfriendly and channel degradation. The channel or path of the data link can be degraded by various factors such as; jammers, atmospheric changes, blockage from obstacles like hills, buildings or other, and multipath. All of these factors can reduce the desired signal level or increase the noise which can degrade the signal level or QoS. In addition, broadband noise can degrade the data link by the adjacent equipment that raises the noise floor which causes the data link to have insufficient signal-to-noise ratio, S/N.
There are several cognitive techniques that can be used to mitigate the effects of jammers and channel degradation to improve the QoS of the data link. Some of the basic techniques include; Dynamic Spectrum Allocation DSA, Power Gain Control, Waveform including Types of Modulation, Spread Spectrum and Error Correction, Adaptive Filters, Cosite RF Tunable Filters, Dynamic Antenna Techniques using AESAs including Multiple In Multiple Out MIMO, and Network Configurations including Multi-hop adhoc meshed networks, forming, self-healing and others. This presentation addresses these cognitive techniques and provides multiple solutions and system tradeoffs to provide the optimal solution using the available capabilities.