27
CHAPTER 2: Introduction
2.4 System-Bandwidth Utilization
Tables 1-1 and 1-2 below and on the next page list the bandwidth available to the
DVM data channel as a function of the number and digitizing rate of the voice
channels:
• Table 1-1 provides the data-channel bandwidths for the adaptive and non-
adaptive 1 modes. Under Idle Voice Channels, you will find the bandwidth
available, in the adaptive mode, for the data channel when both voice
channels are idle.
• Table 1-2 provides the bandwidths for the non-adaptive 2 mode (this mode is
intended for equipment limited to operation at standard data rates).
Table 2-1. Data-Channel Bandwidth in Kilobits per Second as a Function of
Voice-Channel and Main-Link Rates for Adaptive Mode and Non-Adaptive
Mode 1
Main-
Data-Channel Bandwidth (kbps) vs.
Idle Voice
Link
Voice-Channel Digitizing Rate (kbps)
Channels
Data
One Voice Channel
Two Voice Channels
(Adaptive
Rate
4.8
6.4
7.2
9.6
12.8
4.8
6.4
7.2
9.6
12.8
Mode Only)
9.6
4
2.4
1.6
—
—
—
—
—
—
—
8.8
12
6.4*
4.8
4
1.6
—
1.6
—
—
—
—
11.2
14.4
8.8
7.2*
6.4
4
0.8
4
0.8
—
—
—
13.6
16.8
11.2
9.6*
8.8
6.4
3.2
6.4
3.2
1.6
—
—
16
19.2
13.6
12
11.2
8.8
5.6
8.8
5.6
4
—
—
18.4
21.6
16
14.4*
13.6
11.2
8
11.2
8
6.4
1.6
—
20.8
24
18.4
16.8
16
13.6
10.4
13.6
10.4
8.8
4
—
23.2
26.4
20.8
19.2*
18.4
16*
12.8
16*
12.8
11.2
6.4
—
25.6*
28.8
23.2
21.6
20.8
18.4
15.2
18.4
15.2
13.6
8.8
2.4
28
32
26.4
24.8
24
21.6
18.4
21.6
18.4
16.8
12
5.6
31.2
38.4
32.8
31.2
30.4
28
24.8
28
24.8
23.2
18.4
12
37.6
48
41.6
40
39.2
36.8
33.6
36.8
33.6
32
27.2
20.8
46.4
56
49.6
48*
47.2
44.8
41.6
44.8
41.6
40
35.2
28.8
54.4
64
57.6
56*
55.2
52.8
49.6
52.8
49.6
48*
43.2
36.8
62.4
112
105.6
104
103.2
100.8
97.6
100.8
97.6
96*
91.2
84.8
110.4
128
121.6
120
119.2
116.8
113.6 116.8 113.6
112*
107.2 100.8
126.4
192
184
182.4
—
179.2
176
179.2
176
174.4 169.6 163.2
188.8
256
248
246.4
—
243.2
240
243.2
240
238.4 233.6 227.2
252.8
* In the non-adaptive 1 mode, these configurations yield standard data rates on the data channel,
that can be used in addition to the data rates available in the non-adaptive 2 mode.
Содержание MX270A
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