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| n |
Random
Access Channel
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initiate
calls, send short messages, respond to paging
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messages,
initiate location updates
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shared
among all mobiles, use slotted Aloha
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messages
are short (87 bits) to fit into one burst
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use
random 5-bit sequence to distinguish messages
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mobile
transmits, wait for acknowledgement (including
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5
bits and info about SDCCH for further signaling)
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if
two stations choose same sequence, transmit in same
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interval,
and one signal is stronger than the other: base
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will
acknowledge receipt, both handsets will tune to
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same
traffic channel (use call mgmt procedures)
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