User's Manual Chapter 13

Base FCC Regulatory Test Report
7-102
AT&T Wireless Services
FCC Type Acceptance Application
10991 Rev. 1.0 7/6/99
7.2.6 PWAN High-Speed Data Services
7.2.6.1 Basic Data Service Allocation Definition
High speed data services are supported over a group of 32 dedicated
FTRs in each subband known as a Basic Data Service Allocation
(BDSA). All Bases are provisioned for at least one BDSA.
Figure 7.13— shows the default location of the BDSA in the resource
matrix. If required, a Base can be provisioned for a second BDSA,
which by convention will utilize TDMA slots four and five across all 16
FDMA slots.
Each BDSA is subdivided into eight clusters of four FTRs which form
a Logical Data Channel (LDC) or “data quad”. Each LDC supports an
airlink data rate of 72 kbps (refer to Figure 7.15—)
Figure 7.15—Basic Data Service Allocation
7.2.6.2 PWAN Data Traffic Channel (DTch) Definition
The Data Traffic channel (DTch) referenced earlier in the PWAN OSI
Model (Figure 7.7—) is defined as 1 of N downlink LDCs and 1 of M
uplink LDCs. In other words, the number of LDC resources allocated to
the DTch is dynamic according to bandwidth requirements, and the
number of LDCs utilized for each direction of the link may be allocated
independently.
Each Base is provisioned with one primary LDC allocation. Primary
LDCs are distributed among cell sites in a reuse pattern of eight to
minimize co-channel interference. The downlink primary LDC
provides data service control functions and delivers user data at 72
kbps. The uplink primary LDC provides a multiple access, contention-
T6
T7
Basic Data Service Allocation (BDSA0)
F10 F11
6a
6b
6c
6d
F8 F9
5a
5b
5c
5d
F6 F7
4a
4b
4c
4d
F4 F5
3a
3b
3c
3d
F0 F1
1a
1b
1c
1d
F12 F13
7a
7b
7c
7d
F14 F15
8a
8b
8c
8d
F2 F3
2a
2b
2c
2d
72 kbps Logical Data Channel (LDC)