[STDS-802-16] Broadcast
Section 6.1 of the standard states that " In addition to individually
addressed messages, messages may also be sent on multicast connections
(control messages and video distribution are examples of multicast
applications) as well as broadcast to all stations."
Correct me if I'm wrong, but broadcast transmission is limited to MAC
management messages (MAPs, DCD,...) and can't be used to transfer data.
Therefore, the only way to broadcast data is to form a multicast group
containing all SS's
Eyal
-----Original Message-----
From: owner-stds-802-16@listserv.ieee.org
[mailto:owner-stds-802-16@listserv.ieee.org]On Behalf Of Don Leimer
Sent: Monday, April 19, 2004 8:26 PM
To: STDS-802-16@listserv.ieee.org
Subject: Re: [STDS-802-16] Clarification regarding SS power level control
Only one more comment. The final 4dB of error will also be reduced by
subsequent BS commands, and relative error diminishes to +/- 0.5dB for
the final error (relative to the BS's capability to measure power)
-----Original Message-----
From: Raja Banerjea [mailto:RBanerjea@PROXIM.COM]
Sent: Monday, April 19, 2004 9:14 AM
To: STDS-802-16@LISTSERV.IEEE.ORG
Subject: Re: [STDS-802-16] Clarification regarding SS power
level control
The power control method is a closed loop method where the
Base station asks for further power control corrections if
required. If the base station requests the subscriber station
in the RNG-RESP to increase the power level by 30dB the SS
should increase it by 30dB with a relative accuracy of 4dB.
If the Base station is going to increase the power of the SS
in 5 steps and the BS requests the SS to increase the power
by 8dB the SS will increase it by 8dB with a relative
accuracy of 4dB. In the subsequent RNG-RESP message the BS
instead of requesting a power increase of 8dB will request
for 8dB+(relative accuracy). Therefore after each increase
requested from the BS the relative accuracy should be 4dB.
This assumes that the BS can make an accurate measurement of
the SS's power increase.
Any comments ?
Regards,
-Raja
-----Original Message-----
From: Crozier, Eugene
[mailto:Eugene_Crozier@SRTELECOM.COM]
Sent: Monday, April 19, 2004 6:26 AM
To: STDS-802-16@listserv.ieee.org
Subject: Re: [STDS-802-16] Clarification
regarding SS power level control
My understanding of this is that the step size
should be greater than 1 dB but less than 8 dB
(I'd assumed for the relative accuracy that the
50% of the step size can be no more than 4 dB),
but the number of steps is based on the step size
and the relative accuracy to achieve the minimum
control range, so for 1 dB steps, the number of
steps can be between 60 and 20 (30/0.5 and
30/1.5) for a 30 dB range, and for 8 dB step size
the number of steps between 8 and 3 for the 30 dB
range.
Regards
Eugene Crozier
-----Original Message-----
From: Eyal Verbin
[mailto:everbin@AIRSPAN.COM]
Sent: Monday, April 19, 2004 8:22 AM
To: STDS-802-16@listserv.ieee.org
Subject: [STDS-802-16] Clarification
regarding SS power level control
Power level control for the OFDM PHY
is defined in section 8.3.9.1:
" For an SS not supporting
subchannelization, the transmitter
shall support a monotonic power level
control of 30 dB minimum. For an SS
supporting subchannelization, the
transmitter shall support a monotonic
power level control of 50 dB minimum.
The minimum step size shall be no
more than 1 dB. The relative accuracy
of the power control mechanism is
+/-50% of the step size in dB, but no
more than 4 dB. As an example, for a
step size of 5 dB the relative
accuracy is 2.5 dB. For a BS, the
transmitter shall support a monotonic
power level control of 10 dB
minimum."
Looking at the SS (subchannelization)
for example, it is possible to go
from Min power to Max power either in
5 steps of 8 dB or in a single step
of 50dB. In the first option the
accumulated offset can reach 5*4dB
(20dB) wheras in the second option
the tolerance is limited to 4dB.
Does anyone have a more clear
interpretation of this text?
Eyal Verbin