Although simultaneous multithreading (SMT) has been shown being an efficient technique to improve processor performance, little work has been done on real-time SMT scheduling. The objective of this paper is to explore realtime SMT scheduling, for independent periodic task sets with schedulability guarantees. We propose emulation-based scheduling algorithms with and without task migration to emulate an adjustable SMT processor over a non-adjustable SMT processol: The schedulability tests for the proposed scheduling algorithms are presented. An approximation bound on the average number of tasks running in parallel is also shown. The performance of the proposed algorithms was evaluated by a series of simulation experiments.