ABSTRACT
Radio Data System (RDS) data groups are referred to by both the group type and version, that is, OA and 14B. The "A" and "B" versions differ only in the coding of the data for the group, as RDS data is divided into functional groups that share a common structure but perform different functions. After the RDS signal is modulated and demodulated as a synchronous bit stream, this bit stream or endless stream of logical 1's and 0's are structured into a baseband code. All data groups share a common fixed structure of information coding to allow critical data to be transmitted in a fixed, highly repetitive pattern to ensure the best reception, even under adverse reception conditions. The group type code defines the basic feature function of the data group. The operator can select from these group types and transmit all or only a portion of them, depending upon the features in use.
