{"product_id":"emax-pagoda-2-antenna-5-8g-80mm-8cm-rhcp-red-omnidirectional-omni-fpv-flat-panel-sma2pcs","title":"★EMAX Pagoda 2 Antenna 5.8G 80mm 8cm RHCP Red Omnidirectional Omni FPV Flat Panel SMA(2pcs)","description":"\u003ch2\u003e \u003c\/h2\u003e\n\u003ch2\u003e \u003c\/h2\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003eCenter frequency: 5.8 GHz\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eBandwidth: 500 MHz (5.55 – 6.05 GHz)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eMatching: S11 \u0026lt; -20 dB, VSWR \u0026lt; 1.22 (at center frequency)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eAxial ratio: \u0026lt; 1.3\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eRadiation efficiency: 95%\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eOriginally the radiation efficiency was listed as 92%, this was a mistake. These values are based on simulation, actual measurements are below (they are very similar). The center frequency may shift a bit between batches as a result of variations in the dielectric constant of FR4. Also, not all brands of FR4 have the same dielectric constant. Frequency shifts up to 100 MHz are normal.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ch3\u003eRadiation pattern\u003c\/h3\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0469\/7358\/3518\/t\/3\/assets\/pagoda2-rad-3d-l80-wp-30db-small.png?v=1598534553\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ci\u003e3D radiation pattern. Look at the 2D version if you actually want to see the numbers.\u003c\/i\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0469\/7358\/3518\/t\/3\/assets\/pagoda2-model-small.png?v=1598534555\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ci\u003eSimulation model.\u003c\/i\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0469\/7358\/3518\/t\/3\/assets\/pagoda2-rad-vert-l80-wp-small.png?v=1598534557\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ci\u003eBest case, vertical cross-section taken at various angles.\u003c\/i\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0469\/7358\/3518\/t\/3\/assets\/pagoda2-rad-vert-l80-nowp-small.png?v=1598534559\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ci\u003eWorst case, vertical cross-section taken at various angles.\u003c\/i\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0469\/7358\/3518\/t\/3\/assets\/cloverleaf-model-small.png?v=1598534561\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ci\u003eSimulation model.\u003c\/i\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0469\/7358\/3518\/t\/3\/assets\/cloverleaf-rad-vert-l80-wp-small.png?v=1598534563\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ci\u003eBest case, vertical cross-section taken at various angles.\u003c\/i\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0469\/7358\/3518\/t\/3\/assets\/cloverleaf-rad-vert-l80-nowp-small.png?v=1598534564\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ci\u003eWorst case, vertical cross-section taken at various angles.\u003c\/i\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003eThe 'best case' and 'worst case' correspond to different assumptions about what happens to signals that travel along the outside of the coax. In the 'best case' simulation, these are completely absorbed at the other end of the coax. In the 'worst case' simulation, they are completely reflected back towards the antenna. The latter case usually results in standing waves on the outside of the coax, which causes the coax itself to radiate and interfere with the radiation pattern of the antenna. This is why the radiation pattern isn't smooth anymore. The reality will be somewhere between these two extremes.\u003c\/p\u003e\n\u003ch3\u003eMeasurements\u003c\/h3\u003e\n\u003cp\u003e\u003cimg alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0469\/7358\/3518\/t\/3\/assets\/pagoda2-vna-s11-small.png?v=1598534565\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ci\u003eVNA measurements.\u003c\/i\u003e\u003c\/p\u003e","brand":"emaxmodelstore","offers":[{"title":"80mm \/ RHCP(Red) \/ SMA","offer_id":35882633560222,"sku":"0109002007","price":13.84,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0469\/7358\/3518\/products\/qq_20170608162432.png?v=1598534551","url":"https:\/\/shop.emaxmodel.com\/products\/emax-pagoda-2-antenna-5-8g-80mm-8cm-rhcp-red-omnidirectional-omni-fpv-flat-panel-sma2pcs","provider":"Emax","version":"1.0","type":"link"}