High-end Camera Coupled Radiated Emission Analysis for Mobile Handsets

Yongsup Kim, Jungmin Kim, Dongsoon Lim, Austin S. Kim Advanced CAE Lab., Samsung Electronics Co. Suwon, Korea, yongsup2.kim@samsung.com

1. Introduction Mobile handset design is getting complicated and all the components are closely neighbouring each other. Almost every audio/video functions are embedded, simply mobile phone goes to mobile computer in terms of hardware design as well as software design. Especially, hardware complexity with high speed signals makes hard to meet EMC specification at the end of development stage. Radiated emission (RE) is one of mandatory EMC testing standard for mobile handset development. As an international EMC testing standard, CISPR22 Class B[1], RE testing is required for all the mobile handset models targeting Europe and China market. Recently, high-end camera module over 10M pixels is getting mounted in the phone. As camera resolution goes up, camera clock rates also increase and meeting the RE specification - 30dBuV/m (30~230MHz) and 37dBuV/m (230~1,000MHz) goes to a quite challenging task. In this paper, a computer aided engineering (CAE) technique analyzing camera coupled noise is addressed. Distinguished coupling noise analysis methodology is introduced and noise enhancement points are validated through simulation data and chamber measurement data. Simulated coupling noise analysis closely matches with measured data and shows costless virtual simulation could considerably shorten burdensome RE debugging time. 2. Camera Coupled Noise Analysis To understand overall EMC phenomenon, EMI scanning is done in advance. Scanned image in figure 2(a) shows EMI noise around camera lens body is densely distributed. There are two clocks to drive camera operations in this handset model. One named as MCLK is provided from MODEM and works as main clock, the other clock named PCLK comes from Image Signal Processor (ISP) IC and works as pixel clock. Both high speed clocks seem to worsen EMC performance.

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The 2009 International Symposium on Antennas and Propagation (ISAP 2009)October 20-23, 2009, Bangkok, THAILAND

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The 2009 International Symposium on Antennas and Propagation (ISAP 2009)October 20-23, 2009, Bangkok, THAILAND

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The 2009 International Symposium on Antennas and Propagation (ISAP 2009)October 20-23, 2009, Bangkok, THAILAND

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The 2009 International Symposium on Antennas and Propagation (ISAP 2009)October 20-23, 2009, Bangkok, THAILAND

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