**5. Platform noise measurement techniques**

Conductive or near-field coupling platform noise will raise the level of RF receiver noise floor and thus cause performance degradation, and thus we need to investigate the isolation required as shown in Figure 23. We will describe the related measurement techniques in this section.

Base on Platform Noise Power define the requirements of Touch Panel Isolation

Fig. 23. Platform noise coupling.

196 Wireless Communications and Networks – Recent Advances

X-2. X-polar pattern, ANT and Panel assembled, panel off

Panel iron case

**4.3 Resonance issues of mechanic structure** 

Fig. 22. Antenna radiation coupling.

transfering to the LVDS cable.

mini-coaxial cable.

methodology.

section.

Energy distribute along the Y-direction of the iron case

> Energy increased around this area i.e. Power module noise will be easy picked up

The LCD panel of Notebook and the enclosure or PCB would usually create a resonant structure. The related resonance issue could be explained with the following measuring

1. Connect port 1 of network analyzer to LVDS cable and WEB camera cable via a coupling fixture ( Balun and low-mu ferrite core as absorbing clamp) for energy

2. Connect port 2 of network analyzer to the embedded antenna of Notebook via its own

3. Measure the VSWR of port 1 and port 2 respectively. Both VSWR must be less than 2.5

When enclosure of LCD panel was removed, the maximal difference of S21 mentioned above can reach upto 20dB. Hence we can conclude that LVDS and Web camera cables, embedded antenna and its mini-coaxial cable, LCD panel all will lead to amplification of

Conductive or near-field coupling platform noise will raise the level of RF receiver noise floor and thus cause performance degradation, and thus we need to investigate the isolation required as shown in Figure 23. We will describe the related measurement techniques in this

to ensure the testing setup is good enough for efficient energy transfer.

coupling between the interference sources and receiving module.

**5. Platform noise measurement techniques** 
