Table of Contents
Advertisement
2.6.7
Modulation accuracy (EVM), OFDM rates
The following table lists the EVM requirements for OFDM data rates which use 802.11a, 802.11g, and 802.11n
draft 2.0 waveforms:
Modulation
BPSK
QPSK
QPSK
16-QAM
16-QAM
64-QAM
64-QAM
64-QAM
2.6.8
Phase noise
Normally, the phase noise effect has already part of the transmit EVM specifications. However, the receiver local
oscillator can still affect the receive signal quality.
2.6.9
VCO turn around settling time
The VCO shape should be similar to the plot below or better for backward compatibility with older Motorola
products. Specifically, during transient transition from transmit to receive, or from receive to transmit, the VCO
frequency shall not change more than 20 KHz over 20us counting from the start of the turnaround packet.
2
5.5
11
Figure 9- Transmit modulation accuracy (EVM) for DSSS rates
Data rate(Mbps)
Relative constellation error (dB) (minimum)
6
9
12
18
24
36
48
54
Figure 10-EVM specifications for OFDM 802.11 a/g rates
Code rate
Relative constellation error (dB) (minimum)
½
½
¾
½
¾
½
¾
5/6
Figure 11-Transmit modulation accuracy (EVM) for HT rates
Item
Integrated phase noise
Figure 12-Phase noise specification
For Internal Use Only - Do Not Duplicate
Copyright (c) 2009 by Motorola
CONFIDENTIAL AND PROPRIETARY
35%
35%
35%
-5
-8
-10
-13
-16
-19
-22
-25
-5
-10
-13
-16
-19
-22
-25
-28
Max
Unit
1.5
Degree rms
11
Advertisement
Table of Contents
