Agilent Technologies N1911A Manual do Utilizador descarregar pdf (Página 12)

Power vs. Time (PvT)

This measurement examines time

domain burst structure and make mea-

surements over certain subframes.

P-Series power meter real time marker

allows the user to manually move

the marker to measure the desired

subframe burst.

Figure 9 shows the captured power vs

time of the WiMAX signal. 5 ms frame

duration (refer to waveform setup on

Page 10) was initially set. P-Series

power meter of capturing the whole

WiMAX burst signal.

In IEEE 802.16, there is no speciﬁ c

deﬁ nition for power. Thus, users are

required to specify the design of the

frame based on their measurements.

The Signal Studio under Downlink step

reveals that the frame duration of 5

ms (see Figure 10). Moving the cursor

around the frame zone reveals the

time duration and power level of the

Preamble, DL, TTG, UL & RTG as seen

below:

• Preamble = 0.104 ms / 1 sym

• DL = 2.06 ms / 20 sym(s)

• TTG = 0.34 ms

* UL = 1.85 ms / 18 sym(s)

• RTG = 0.648 ms

The Preamble region (Figure 10)

shows the 0 dB. In DL zone, there are

3 different power levels:

i) –3.98 dB when the FCH and Burst 1

is ON (just after the Preamble)

ii) –4.46 dB when only Burst 1 is ON

ii) –10.27 dB from the end of burst 1 to

the end of the DL zone.

Measuring Downlink (DL) Waveform

Instructions Keystrokes

On the P-Series:

1. Select the WiMAX predeﬁ ned

preset value.

[Preset], Press [ or ] key to

choose {WiMAX}. [Select], {Conﬁ rm}.

2. Set the trace display. [Disp], {Disp Type}, {Trace}.

3. Set the trigger holdoff 4 ms. [Trig/Acq], {Settings}, {1 of 2}, {Hold-

off 4 ms}.

4. Expand the window. Change the

scale. Move the marker to

measure the frame duration

(See Figure 9).

[ ], {Trace Control}, {X Start

-400 µs, X Scale 600 µs & Y Scale

10 dB} {Gate Control}, press [

] to allocate marker 2 and [ ] to

allocate marker 1.

Figure 9 WiMAX waveform duration at 5 ms for DL in TDD

mode. In the P-Series power meter, green lines (denote

Gate1 and Gate2) are used to highlight the burst structure

of the WiMAX proﬁ le.

Figure 10 Frame duration (5 ms) of DL waveform captured from Signal Studio

1 2 ... 7 8 9 10 11 12 13 14 15 16 17 ... 25 26

Comentários a estes Manuais

Sem comentários

Agilent Technologies N1911A Manual do Utilizador Página 12

Comentários a estes Manuais

Manuais e produtos relacionados com Multímetros Agilent Technologies N1911A