Nokia Mobile Phones Limited

Nokia Corporation

Sona Kapadia

Zhi-Chun Honkasalo

John W Noneman

Pasi Liimatainen

John Noneman

In a packet data transmission and reception system, a media access control (MAC) message is broadcast by a base station to a plurality of mobile stations. The MAC message contains packet data transmission scheduling information which allows the base station to preemptively control mobile station access to traffic channels in order to maximize the efficiency of packet data transmissions and allow scheduling consideration including priority access, quality of service and maximum bytes per transfer. The MAC message consists of a control frame structure, which comprises scheduling parameters including MAC IDs fields, activity fields, and a field representing the number of free traffic channels in a cell. These parameters enable multiple mobile stations to share, in a time multiplexed fashion, traffic channels for packet data transmission on CDMA based mobile communication systems.

Method for scheduling packet data transmission

In a packet data transmission and reception system a media access control (MAC) message is broadcast by a base station to a plurality of mobile stations. The MAC message contains packet data transmission scheduling information which allows the base station to preemptively control mobile station access to traffic channels in order to maximize the efficiency of packet data transmissions and allow scheduling consideration including priority access, quality of service and maximum bytes per transfer. The MAC message consists of a control frame structure which comprises scheduling parameters including MAC IDs fields, activity fields, and a field representing the number of free traffic channels in a cell. These parameters enable multiple mobile stations to share, in a time multiplexed fashion, traffic channels for packet data transmission on CDMA based mobile communication systems.

A method and means of modifying the multi-rate high speed data CDMA system by increasing the physical layer data rate to n times the basic IS-95 rate, while not increasing the frame size proportionally to avoid the use of larger frames, and varying the data rate by changing the number of frames, N, transmitted during each period of T sec, using the relationship R=N.times.F/T, where R bps is the physical layer data rate, F bits is the physical layer frame size, and T sec is the frame period and the interleave depth. Using this approach, the data rate can be varied between F/T bps and N.times.F/T bps using the same set of allowed frame sizes. Further, a major frame of data is formed using a fixed number of minor frames in combination, which minor frames are full rate and simple fractions of a full rate, i.e., 1/2 rate, 1/4 rate, and 1/8 rate. A basic data rate is established which is the data rate that will use a single full rate frame. The sizes of the minor frames needed to generate a major frame are determined by dividing the desired data rate by the basic data rate to form a ratio, the integer portion of which ratio indicates the number of full rate frames and the fractional portion of which determines the size of the single fractional rate frame to use. The full rate frames are concatenated with the single fractional rate frame to produce the final frame structure that is transmitted.

Framing technique for a multi-rate CDMA communication system

In a packet data transmission and reception system two inactivity time intervals are used along with a variable data rate including an idle rate, a default or intermediate rate, and a peak rate. When no packet data is available the data rate is reduced to an idle rate to free most of the system capacity used for communicating the packet transmissions. The packet data service connection is thus maintained and the idle rate transmission of idle packets allows the receiving end of the channel to stay synchronized with the transmitter. If the packet data transmission resumes before the first inactivity timer expires the transmission rate returns immediately to the peak rate. However, if the inactivity continues until the first inactivity timer expires, the data rate is preferably not immediately returned to the peak rate. The packet data service connection is instead maintained at the idle rate after the first inactivity timer expires. When the second inactivity timer expires the packet data service is released. If packet data becomes available for transmission between the time the first inactivity timer expires and the second inactivity timer expires, the data packets are transmitted at the intermediate rate, which is generally lower than the peak rate. After the transmitting source receives an acknowledgment from the receiving end of the channel, the data rate switches back to the peak rate.

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