PLMN. Public land mobile network. A cellular wireless carrier. Ugly and confusing phrase but used throughout the GSM community. All cellular systems are land mobile networks but I'm not sure that all PLMNs are cellular. Info on private land mobile is here. Barred cell. A cell removed from service for testing or other reasons. BCCH. As discussed. The Broadcast Control Channel. Operates on the downlink, that is from the base station to the mobile. FCB: Frequency control bits. Discussed here. BSIC: Base station identity code. Identifies the cellular carrier and the base station the mobile is connecting to. As discussed here. Path loss.
The diagram above is reprinted with permission of Clint Smith.
At this point I must turn you over to the GSM article I've annotated. I need more time to figure out how many more details I should put into this article. Smith's diagrams show that our call processing discussion is just about finished. I hadn't planned on writing about handoffs or authentication. For an overview of those topics, just click on the links. Best, Tom Farley
Terms
"Interference is like the voices of other people in the room; if they are speaking at a high volume your friend will not be able to distinguish your voice. Path loss, on the other hand, results from the appearance of objects (e.g. a vase, table, or door) between you and your friend. Of course, in the context of wireless communications, path loss is caused by much larger objects like hills, buildings, and so forth. If the channel conditions (path loss and interference) in the crowded room are poor, you can attempt to communicate with your friend by shouting, or by using very simple words or hand signals. Another option is to wait for everyone else to quiet down or move to another part of the room. This is analogous to what we try to do for wireless devices if conditions are poor, we can raise the transmitter power (start shouting), reduce coding complexity (use simpler words), or withhold transmission until the channel improves." Tim Holliday
From: http://sll.stanford.edu/
projects/i-rite/body_holliday.html
VII GSM Call Processing: (1) Introduction / (2) The Radio elements/ (3) The Network or Switching elements / (4) Main discussion
