Ovrrbu-bts. Pdf
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1/30/00 BASE TRANSCEIVER STATION Release 1.00 2 - 15 1.6.7 Call Processing When an SU detects an off-hook (the user has picked up the phone), it will transmit an outgoing call request on one of the 6 reverse synchronous side channels in a Slotted ALOHA fashion. The side channel is chosen at random. The RBU will process this request and, providing an active channel is available, send an outgoing call reply to the SU which contains the active channel codes (both forward and reverse). In the meantime, the RBU will begin to transmit forward side channel data on the newly activated channel and at a given time, begin to transmit the active call data. The SU, which is listening to the forward side channel, will receive the active channel assignment and switch at a superframe boundary to the active codes. It will begin to receive the side channel data and then the active call data. When an incoming call is received by the DSCO for one of the SUs in the local loop, the RBU will be notified. The RBU will first check to see if the intended SU is busy. If not, the RBU will send a message to the SU on the forward side channel that contains the active channel codes. The process then continues the same as the outgoing call processing discussed above. If all channels are busy and the DSCO receives an incoming call for a non-busy subscriber, it provides a subscriber busy tone to the caller unless the called SU has priority inbound access (like a hospital, fire station, or police), in which case the DSCO will instruct the RBU to drop the least priority call to free up a channel for the called SU. Similarly, if an SU initiates request for service and no traffic channels are open, then the RBU provides the dial tone on a side channel and receives the dialed number. If the dialed number is an emergency number then the RBU drops a least priority call to free up a traffic channel and connect it to the SU. If the called number is not an emergency number then the SU is provided a “softbusy” tone indicating a “wait for service” condition. 1.6.8 OAM&P Eagle Management Suite discussed earlier provides Operations, Administration, Maintenance, and Provisioning (OAM&P) functions. It is a software module that needs a Pentium II / 266MHz PC or better running Windows NT ® with English language interface. It can be on dedicated hardware or co-resident with a compatible hardware platform running the Administration Terminal (AT) for the DSCO. The EMS can communicate with the DSCO using an RS232 interface or a LAN connection (like Arcnet or Ethernet) and can also be connected to an RBU using an RS232 connection. |