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AIR INTERFACE FOR FIXED BROADBAND WIRELESS ACCESS SYSTEMS

IEEE Std 802.16-2001

8.2.6.3.10 Summary of uplink PHY parameters

Table 111 summarizes the uplink PHY parameters.

 

Table 111—Summary of uplink PHY parameters

 

 

 

 

 

Reed-Solomon over GF(256)

 

 

Information byte lengths: 6–255 bytes

Outer Coding

 

Error correction capability R = 0–32 (T = 0–16)

 

 

BTC (optional)

 

 

NOTE—There is no inner code selected in this case.

 

 

 

 

 

Selectable from the following options:

Inner Coding

 

None

 

(24,16) block convolutional code

 

 

 

 

(9,8) parity check code (optional)

 

 

 

Randomization

 

x15 + x14 +1

 

Scrambler Seed: 15-bit programmable

 

 

 

 

 

Preamble

 

Based on repetition of 8 symbol or 16 symbol CAZAC sequences

 

 

 

Modulation

 

QPSK (mandatory);16-QAM (optional); 64-QAM (optional)

 

 

 

Spectral shaping

 

α = 0.25

 

 

 

8.2.7 Baud rates and channel bandwidths

A large amount of spectrum is potentially available in the 10–66 GHz range for point-to-multipoint systems. Although regulatory requirements vary between different regions, sufficient commonality exists for a default RF channel bandwidth to be specified for each major region. This is necessary in order to ensure that products built to this standard have interoperability over the air interface.

Systems shall use Nyquist square-root raised cosine pulse shaping with a roll-off factor of 0.25 and shall operate on the default RF channel arrangement shown in Table 112. Note that baud rates are chosen to provide an integer number of PSs per frame. The frame duration choice compromises between transport efficiency (with lower frame overhead) and latency.

Table 112—Baud rates and channel sizes for a roll-off factor of 0.25

Channel size

Symbol rate

Bit rate

Bit rate

Bit rate

Recommended

Number of

(Mbit/s)

(Mbit/s)

(Mbit/s)

(MHz)

(MBaud)

Frame Duration (ms)

PSs/frame

QPSK

16-QAM

64-QAM

 

 

 

 

 

 

 

 

 

 

 

20

16

32

64

96

1

4000

 

 

 

 

 

 

 

25

20

40

80

120

1

5000

 

 

 

 

 

 

 

28

22.4

44.8

89.6

134.4

1

5600

 

 

 

 

 

 

 

Due to wide variations in local regulations, no frequency plan is specified in this standard. No single plan can accommodate all cases. For example, the 24.5-26.5 GHz band in Europe is regulated by CEPT requirements concerning specific duplex spacing and rasters. This does not match a similar spectrum allocation in North America.

Copyright © 2002 IEEE. All rights reserved.

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