User's Manual Part 1
Release8OverviewofCycloneNetworks
Issue2,November2007 Draft5forRegulatoryReview 83
c. the AP sends a Registration Grant to the SM.
If BAM is not configured on the AP or the AP is not licensed for authentication,
then the AP simply returns the Registration Grant to the SM.
This Registration Grant includes the distance between the AP and SM. The SM uses the
distance to distinguish when to transmit data in the uplink frame. The AP performs
advance scheduling of up to 1024 frames that each SM will be permitted to use in the
uplink frame.
7.1.4 MediaAccessControlandAPCapacity
Regardless of whether the maximum number of SMs (200) all request service at the
same time, the reservation Media Access Control (MAC) system allows the AP to give a
reservation slot to each SM that requests service.
Regardless of the distance between any SM and the AP, the reservation MAC system
ensures that all SM data slots are free of contention. For this reason
• all SMs are equally able to compete for uplink and downlink bandwidth.
• the capacity of the AP is not degraded by distance from the SMs.
7.1.5 CycloneSlotUsage
The frame illustrated in
Figure 18 shows both packet fragments (yellow) and unused slot
space (red) typical of uplink traffic. Packet sizes smaller than 64 bytes cause unused slot
spaces.
Figure 18: Uplink data slot usage
The following statistics apply to Cyclone frame slot usage:
• Slot capacity is 64 bytes.
• The optimum Ethernet packet size is 1518 bytes.
• The maximum downlink throughput for one AP to one SM is 1800 packets per
second (pps).
• The maximum uplink throughput for one AP to one SM is 300 pps.
• The maximum backhaul throughput is 3000 pps.
7.1.6 DataTransferCapacity
Cyclone modules use Time Division Duplex (TDD) on a common frequency to divide
frames for uplink (orange) and downlink (green) usage, as shown in
Figure 19.