TABLE OF CONTENTS The alternate UWB concept to DS is based on orthogonal frequency division modulation (OFDM) modulation as discussed in Chapter 6. For the purpose of operation, the UWB spectra of Figure 13.1 is broken into five band groups. The first four groups have three subbands, and the fourth has two subbands. Figure 13.11 shows this assignment. The use of these bands is discussed in the section on RF modulation below (Section 13.2.3). Table 13.12 gives the specific frequency assignments for each.
| Band Group | BAND_ID | Lower Frequency (MHz) | Center Frequency (MHz) | Upper Frequency (MHz) |
|---|---|---|---|---|
| 1 | 1 | 3,168 | 3,432 | 3,696 |
| 2 | 3,696 | 3,960 | 4,224 | |
| 3 | 4,224 | 4,488 | 4,752 | |
| 2 | 4 | 4,752 | 5,016 | 5,280 |
| 5 | 5,280 | 5,544 | 5,808 | |
| 6 | 5,808 | 6,072 | 6,336 | |
| 3 | 7 | 6,336 | 6,600 | 6,864 |
| 8 | 6,864 | 7,128 | 7,392 | |
| 9 | 7,392 | 7,656 | 7,920 | |
| 4 | 10 | 7,920 | 8,184 | 8,448 |
| 11 | 8,448 | 8,712 | 8,976 | |
| 12 | 8,976 | 9,240 | 9,504 | |
| 5 | 13 | 9,504 | 9,768 | 10,032 |
| 14 | 10,032 | 10,296 | 10,560 |
The details of the first line in Table 13.13 are as follows:
Input data rate: 160/3=53.3 Mbs;
QPSK modulation, 2 bits/sym: 80/3=Msym/sec;
Rate 1/3 FEC: [80/3]*3 80 Msym/sec;
OFDM time: 0.3125 usec;
Required data symbols per OFDM frame: 0.3125 usec*80 Msym/sec=50;
Conjugate addition: yes;
Available data symbols per OFDM frame: 2*25=50.
| Data Rate (Mbps) | Modulation | Coding Rate (R) | Conjugate Symmetric Input to IFFT | Time... |
|---|
