[802-20-GENERAL:] Subject: Alternate Text Section 11 Link Budget
All,
First I’d like to thank Anna for taking the time to wrap up the section on the link budget..
My position is that the link budget should be taken as a summary of the inputs into each proponent’s simulation. Section 12 in
Eval_Criteria_ver13a-track-change (http://grouper.ieee.org/groups/802/20/DropBox/Eval_Criteria_ver13a-track-changes.doc) already
adequately allows us to compare the ability of technologies to tradeoff cell size vs service levels vs load.
For example, by reading off the low load intercept in “Figure 10: Contours of constant minimum service level” on page 40, one can read off
the “maximum range” that a system supports when say users achieve a certain data rate 90% of the time. Therefore I see no reason to
require the link budget to be more a collection of required inputs for each proponent’s simulations and otherwise optional informative
material (see below).
From "Eval_LinkBudget1":
The link budget template as adopted from ITU-R M.1225 with slight modifications in Table 11.1 should be used for computing the link budget
under the following cellular test environments:
a. Suburban Macro
b. Urban Macro
c. Urban Micro
d. Indoor Pico
The corresponding path loss model as described in the 802.20 channel models document should be used for path loss computation.
The maximum information data rate at the cell boundary that is supported by the proposed technology is used in the link budget computation
to determine the corresponding maximum range or cell size that can be achieved by the technology.
Required Eb/(No+Io) for the corresponding information data rate at the target BER should be taken from the simulation results using the
channel models case I-IV, as specified in the 802.20 channel models document.
The target BER used in the link budget evaluation is stated in section 10.1.2.
Alternate Text:
The link budget template as adopted from ITU-R M.1225 with slight modifications is given in Table 11.1. Entries that have explicit
numerical values in the table (such as power levels, cable losses, etc) shall be used by proponents in their respective system
simulations. Proponents may provide informative values for other entries in the table (such as diversity gain, soft handoff gain etc) as
they may pertain to their respective technology.
Mike