A modem, communications system and method are provided with a transmitter
and a receiver connected to a modem termination system (CMTS) by a medium.
The modem has a memory forming a transmit queue including voice and video.
The modem has a controller for sending data units from the receive queue
to CMTS. The modem requests unsolicited grant service (UGS) from CMTS when
the frame controller detects periodic stream to transmit. Upon detecting a
data accumulation in the receive queue, the controller asserts a queue
indicator. The Modem receives an occasional extra grant per interval and
uses these grants until the queue indicator is not asserted. According to
another feature, during transmission, the modem requests subsequent grants
in a subsequent interval using an extended header having multiple bits for
requesting the multiple grants. The CMTS allocates at least an extra grant
to form a grant burst in response to the request.
