Wimax standards and Security The Wimax

Transmitter Spectral Mask

This test measures the spectral profile of the transmitter to verify that the device is not transmitting excessive energy outside its assigned channel bandwidth. As local regulations will control the WiMAX frequency bands,


dB 0

—25

—32
—50
A B C D MHz


FIGURE 9.6
Transmitter spectral mask.


TABLE 9.4
Spectral Mask Limits Used for Figure 9.6

Channelization (MHz)	A	B	C	D
20	9.5	10.9	19.5	29.5
10	4.75	5.45	9.75	14.75

the IEEE 802.16 specification does not attempt to specify the spectral mask for any operation other than the unlicensed band [11]. Figure 9.6 and Table 9.4 show the spectral mask specification for 802.16 unlicensed band operations.
For the measurement of spectral profile, the DUT is set to transmit valid subframes (preambles followed by data bursts). The DUT spectral output is measured using the test equipment (e.g., spectrum analyzer). The above pro- cedure is repeated for various RF frequencies, modulation types, and power levels.

5.