Evaluation of the usage of Adaptive Coding and Modulation (ACM) mechanism in fixed links in CEPT. This includes the reference modulation and the impact of time varying interference either continuous or of pulse/ burst nature, on Adaptive Coding and Modulation (ACM) mechanism and resulting challenges for the operation of FS. This report is expected to include information on the following elements 

General aspects

• Description of the ACM principle 
• Performances of ACM, e.g time of reaction and thresholds (based on the propagation physics and on data from manufacturers)
• Strategy of implementation for ACM in relation with/without ATPC (based on data from manufacturers)
• Use of ACM for fixed links in CEPT administrations
• Reference modulation(s) in the list of modulations, relation with NFM / FM and planning operations
• Impact of interference (either continuous or pulse/ burst nature) on Band and Carrier Aggregation (BCA) systems with ACM
• Impact of interference (either continuous or pulse/ burst nature) on ACM performance
• Impact of propagation effects in the different FS frequency bands on ACM 
• Impact of the findings on WI43 and WI47
• Impact within a network and on third party links of considering protection levels up to ACM modulation versus the reference modulation only
• Operator's needs in terms of ACM links usage and performance in the network and impact on their network if ACM proper operation cannot be relied
• Mitigation techniques