Singapore's Infocomm Media Development Authority (IMDA) on Monday (May 18) announced the suspension of an ongoing assessment of the proposed consolidation between telco operators M1 and Simba, over the latter's alleged unauthorised use of radio frequency bands.The authority said that the bands are used to provide mobile services, adding that such action is a breach of the Telecommunications Act and also a breach of the conditions of Simba's facilities-based operations licence.The four mobile network operators here are M1, Singtel, StarHub Mobile and Simba Telecom. What are radio frequency bands?Radio frequencies are a part of the electromagnetic spectrum used for wireless communication and signal transmission.Its usage includes: radio, aircraft navigation, marine radio, television broadcasting, mobile networks and even satellite systems.In a consultation paper issued by IMDA in 2014, as part of its proposed amendments to the Telecommunications Regulations, it described radio frequency spectrum as a «scarce resource», requiring management and regulation to ensure efficient allocation and optimal use. Read more