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Sender: "piclist-bounces@mit.edu" Date: Thu, 12 Aug 2021 13:49:54 -0700 Subject: [EE] Modeling radio propagation from antenna mounted in metal robot? Thread-Topic: [EE] Modeling radio propagation from antenna mounted in metal robot? Thread-Index: AdePvVSFPBVraSM2Q2W07b7hkBm9VA== Message-ID: List-Help: List-Subscribe: , List-Unsubscribe: , Reply-To: Microcontroller discussion list - Public. Accept-Language: en-US X-MS-Exchange-Organization-AuthAs: Anonymous X-MS-Exchange-Organization-AuthSource: TS500.efplus4.local X-MS-Has-Attach: X-Auto-Response-Suppress: All X-MS-Exchange-Organization-SenderIdResult: Pass X-MS-Exchange-Organization-PRD: mit.edu X-MS-TNEF-Correlator: received-spf: Pass (protection.outlook.com: domain of gmail.com designates 209.85.214.172 as permitted sender) receiver=protection.outlook.com; client-ip=209.85.214.172; helo=mail-pl1-f172.google.com; dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to; bh=N/XswBlj05DuoRGJXBTXrrvTxKlTryYd1OPcHuKo1VY=; b=eRkTO0NJwoX+eVvZI1tdaqL31tIGVz2HI5xLqFgbPcuzqmlG9iMc11JI89TFEoxy1a ermrCSsgp2pkhmOrMLNcLZTWA9gPoRLPG7oA2xa2+CN5NcM5I+ADHoPfMpyEXc4+RF4q PNwfS55fVfJ4h1raOs2I9SIwJkunqSdjbNmAGMJt6pvVB/ok0fZ7pgwN1s8cNj6Ac0Gf udd99vfeJMxe93CRCXL8lu7cvyqEV/e4fqjAYnlnlx4gYTq1s3qmxHUmu5ikspGDk57f c0muQzk+Ipj4EBmS1uL8qOEsX4AGv/0wJj76UCQxl4bej6VjzdBd0sDXLJNVwIQa1Fod p3Ow== authentication-results: spf=pass (sender IP is 209.85.214.172) smtp.mailfrom=gmail.com; mit.edu; dkim=pass (signature was verified) header.d=gmail.com; mit.edu; dmarc=pass action=none header.from=gmail.com; errors-to: piclist-bounces@mit.edu list-id: "Microcontroller discussion list - Public." list-post: x-beenthere: piclist@mit.edu x-mailman-version: 2.1.6 x-received: by 2002:a62:606:0:b029:3b6:7e9a:fd2c with SMTP id 6-20020a6206060000b02903b67e9afd2cmr5749373pfg.24.1628801430591; Thu, 12 Aug 2021 13:50:30 -0700 (PDT) x-topics: [EE] x-content-filtered-by: Mailman/MimeDel 2.1.6 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Hi everyone, I am building a robot for a local "robotic combat" competition (Ohio Robotics Club, HORD 2021). The robot is essentially a metal cylinder ("full body spinner") with an antenna mounted inside. It can drive upside down and right side up - which forces the single antenna to be recessed into the shell. I am looking for advice on modeling the antenna and the effect of the aluminum enclosure. (maybe point me towards a certain model software with a free trial, or some clever trick to turn the entire chassis into the antenna) I suspect that I will be forced to create apertures in the body of the robot to permit propagation in and out. The robot is roughly 5" in diameter, 1.5" tall, and the frequency is 2.4GHz. I am using an off the shelf RC system with a short 1" whip antenna mounted on a removable coaxial cable. --=20 Jason White --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .