{"id":3301,"date":"2024-02-08T12:29:12","date_gmt":"2024-02-08T12:29:12","guid":{"rendered":"https:\/\/techni3.com\/?p=3301"},"modified":"2024-02-08T12:33:20","modified_gmt":"2024-02-08T12:33:20","slug":"reducing-total-radiated-power","status":"publish","type":"post","link":"https:\/\/techni3.com\/reducing-total-radiated-power\/","title":{"rendered":"Reducing Total Radiated Power"},"content":{"rendered":"\n

Suppressing excessive noise from 22 GHz retimer chips was one matter. Pinpointing the optimal characteristics of a desired solution was another. Read how a global networking technology manufacturer compared nine different simulations and selected Laird\u2122 Eccosorb\u2122 GDS as its ideal, Laird laboratory-confirmed high frequency absorber to reduce total radiated power.<\/em><\/p>\n\n\n\n

Simulations Help Identify \u201cSweet Spot\u201d Microwave Absorber Material for Noisy Retimer and ASIC Chips <\/h2>\n\n\n\n

Server router boards are home to a range of retimer and application-specific (ASIC) chips. Although both chips are sources of troublesome radiated emissions, laboratory simulations now point to solutions which will reduce unwanted noise and improve overall signal integrity.<\/p>\n\n\n\n

In one case at a global networking technology company, retimers functioning at 22GHz transmit fresh copies of signals yet are prone to excessive noise. Initially, gasketing was used to partially suppress retimer and ASIC noise evident in the 20 to 30 GHz frequency range. As data speeds increased, gaskets proved inadequate. The company had also considered metal shielding. However, in router board locations where the heat sink was larger than the chip, the energy would couple through the gap between the router board and heat sink. A novel solution was needed to suppress signal interference.<\/p>\n\n\n\n

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Evaluating absorber solutions <\/h3>\n\n\n\n

The company opted to decrease coupling by replacing gasketing with RF\/microwave absorbers. The material would fit tightly to and surround retimer and ASIC chips in a \u201cpicture frame\u201d configuration, thus improving attenuation of excess noise.<\/p>\n\n\n\n

There were questions – and few specific answers. What would be the best, most effective absorber material to apply in terms of thickness, width, and type? How did changes in material parameters correlate to and affect the fight against excess noise at higher frequencies? What about a solution for lower frequencies?<\/p>\n\n\n\n

For help, the company turned to the in-house simulation and modeling team at Laird, a DuPont business, and its Ansys HFSS full-wave 3D electromagnetic simulation software. Laird would use laboratory simulations to calculate reductions in total radiated power (TRP) and signal loss when evaluating different Laird absorbers with varying parameters.<\/p>\n\n\n\n

Researchers weighed all variables: PCB and heat sink sizes, the distance between the PCB and heat sink, available board space, and absorber thickness and width, as well as magnetic loading. Goals included:<\/p>\n\n\n\n