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Peretz, Vasanth,
I think you may both be confused: Peretz, it would
be useful if you could quote the section from where you derive the idea that the
maps are only sent when they alter. This is not the case
(IMHO).
In the OFDM PHY (section 8.3) the UL-MAP is sent in
every frame, even if it were empty: note the wording in 8.3.5.1: it "shall
immediately follow". (not that I expect it would be empty very often, as
in a quiet network you will still require IR opportunities). The DL-MAP is
not necessarily sent every frame, because the DLFP can contain the
descriptions of up to the first 4 bursts in the frame, but the DL-MAP also
provides additional information that is needed for synchronisation, so must be
sent occasionally (more often than the Lost DL-MAP interval, otherwise the SS
will sign off: again see 8.3.5.1). This is the reason that the DL-MAP is
not always sent.
There are
no sign-in problems for 802.16 equipment: interoperable systems are already
working.
Regards
David
Dr David
Castelow
Airspan Communications Ltd
Principal Systems Engineer
Cambridge House, Oxford Road
DSP & Systems
Design Uxbridge UB8
1UN, UK
http://www.airspan.com
+44 1895 467281
Hi Feder,
Thanks for your reply......
According to my understanding
for e.g. if I select a MAC frame duration
of 10ms, the BS station will send DL-MAP & UL MAP in every DL
subframe (provided the if the MAP messages changes)if I went wrong plz note
me...
UL_MAP:
But,when the BS is initialized and if there are
no SS to receive the MAP messages, in DL subframe period(i.e for every 10
ms completes) the BS has to transmit UL map b'coz the BS has to provide
initial ranging period in UL MAP message so that If any SS receives the MAP
messages will contend & send the RNG-REQ frame & also the BS will not
know when new SS will enter the NW.
DL-MAP:
And let's assume the DL MAP messages are never
changed so the BS will never send the DL-MAP and if any new SS station wants
to enter the NW then it cant be synchronized with the DL channel unless it
receives DLMAP msg???
Sorry for a long mail....If I went wrong plz
correct me
Vasanth
----- Original Message -----
Sent: Wednesday, September 13, 2006
1:10 AM
Subject: Re: [STDS-802-16] UL parameter
acquisition
Actually DL-MAP, UL-MAP shall be sent
whenever the maps are changed.(See 8.3.5.1)
On 9/12/2006
1:43 PM, Peretz Feder wrote:
On
9/12/2006 2:50 AM, Vasanth.Rajan wrote:
Hi all,
I have some doubt in Scanning & UL parameter
acquisition
When the BS is initialized it will send first DL-MAP
frame; my question is following the DL-MAP should
the BS send UL-MAP frame before transmitting DCD & UCD
frames???? DL/UL-MAP goes in every
frame to inform and schedule SS(s).
DCD & UCD are sent every
(configurable) amount of frames.
In STD 802.16-2004,6.3.9.4 Table 114,Message flow during
scanning & UL parameter acquisition process,
Its given that once the SS achives DL syncronization
& obtains the UL channel information and then the BS transmits UL-MAP message...How come the BS know that a
particular SS has Syncronized with DL & obtained
UL channel parameters????so that it could transmit UL-MAP
frame. REG-REQ MAC message
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