Specifications

ETSI
Final draft ETSI EN 300 328 V1.8.1 (2012
-
04)
75
Annex D (informative):
Guidance for testing IEEE 802.11n™ Equipment
D.1 Introduction
The following guidance may be used by test labs and manufacturers when evaluating compliance of
IEEE 802.11n™ [i.4] radio equipment to the present document. The technology-specific information in this annex
does
not
constitute additional requirements and does not modify the technical requirements of the present document.
In addition to the mandatory and optional modes defined in the IEEE 802.11n™ [i.4] technology standard, Smart
Antenna Systems may utilize additional modes of operation not defined in the IEEE 802.11n™ [i.4] standard.
Therefore, this annex presents a non-exhaustive list of the most commonly expected modes and operating states for
IEEE 802.11n™ [i.4] -based equipment with the associated references to the appropriate categories for testing in the
present document.
The guidance provided in this informative annex assumes that the product utilizes two or more transmit and receive
chains.
D.2 Possible Modulations
Listed below are the most common modulation types and channel widths used by 2,4 GHz IEEE 802.11n™ [i.4]
equipment:
• IEEE 802.11™ [i.3] modulations using a single or multiple transmitters with or without transmit CSD.
• HT20: 20 MHz channels with one to four spatial streams (MCS 0 through MCS 76).
• HT40: 40 MHz channels with one to four spatial streams (MCS 0 through MCS 76).
NOTE: A spatial stream is a stream of bits transmitted over a separate spatial dimension. The number of spatial
streams is not necessarily equivalent to the number of transmit chains.
D.2.1 Guidance for Testing
The objective is to test the equipment in configurations which result in the highest e.i.r.p. and e.i.r.p. density. These
configurations are further referred to as the worst-case.
D.2.1.1 Modulation Used for Conformance Testing
One worst case modulation type for 20 MHz operation (and one worst case modulation type for 40 MHz operation, if
supported) should be identified and used for conformance testing per the present document.
Where the 20 MHz and 40 MHz modes support different numbers of transmit chains and spatial streams, testing may
need to be performed to identify the worst case modes.
Comparison measurements of mean RF output power (or mean e.i.r.p.) and Power Spectral Density (or e.i.r.p. density),
across all modulations can be used to establish the worst case modulation type for 20 MHz operation (and the worse
case modulation type for 40 MHz if supported).
EXAMPLE 1: If comparison measurements determine that HT20 MCS 0 (6,5 Mbit/s, one spatial stream) is
worst-case, then this mode should be used for conformance testing (and not IEEE 802.11™ [i.3]
modulations and not HT20 MCS 1 through MCS 15). One worst-case modulation for HT40
operation should be identified and used for the conformance testing.