Channel sequencing using a round-robin scheduler

Abstract

A terminal receives one or more input frames comprising one or more logical channels and may generate one or more output frames including the data received in the logical channels. Each logical channel is dispersed throughout the input frame in one or more timeslots, and each logical channel has an associated buffer. The data of each logical channel received from the timeslot(s) of the input frame(s) is stored in the corresponding buffer. The terminal uses channel sequencing for round-robin scheduling to transfer the data of the received logical channels, if present, in each buffer to one or more output frames. Channel sequencing may apply round-robin scheduling of service of buffers in ascending or descending order of non-empty buffers, accounting for newly filled buffers. Channel sequencing generates a binary word, termed a channels service request (CSR) word, with each bit of the CSR word corresponding to a buffer and indicating whether the buffer requests service. When at least one bit of the CSR word is set, a cycle of round-robin scheduling begins. During a cycle, logic combines the CSR word with a mask to form a masked CSR word, and the mask resets those bits of the CSR word that correspond to newly filled buffers that should be served during the next cycle. The masked CSR word identifies the next, non-empty buffer to be serviced by the buffer server, and the mask generator employs either the CSR word at the beginning of the cycle or the current masked CSR word during the cycle to generate the next mask.