There\u2019s a strange beauty in the way satellites communicate. No wires, no internet cables\u2014just invisible waves passing through space. These signals travel across oceans and continents, carrying important information like satellite health, position, and sometimes even voices.<\/p>\n\n\n\n
For small satellites like PocketQubes\u2014tiny spacecraft that can fit in your hand\u2014the most common way to send and receive signals is through UHF (Ultra High Frequency)<\/strong> and VHF (Very High Frequency)<\/strong>. They\u2019re not as fast as fiber internet, and they\u2019re not the newest technology. But they are simple, reliable, and\u2014when used well\u2014surprisingly effective.”<\/p>\n\n\n\n These radio signals can help us earthlings stay connected with a small spacecraft orbiting hundreds of kilometers above Earth. Sometimes, all we need is a ground antenna, a receiver, and just the right timing as the satellite passes overhead.<\/p>\n\n\n\n Of course, using these radio frequencies for satellite communication usually requires a proper license, depending on national regulations. But the good news is: many countries support educational and amateur radio projects, making it accessible to students, hobbyists, and small teams around the world.<\/p>\n\n\n\n So why are these quiet radio waves still so important? Let\u2019s take a closer look.<\/p>\n\n\n\n Let\u2019s start with the basics. Think of radio frequencies like different lanes on a highway\u2014each lane carries a certain kind of traffic.<\/p>\n\n\n\n VHF<\/strong>, or Very High Frequency, is one of the lower lanes, running from about 30 to 300 MHz. It\u2019s been around for a long time and is used in things you might know, like FM radio stations, communication on ships, and early satellite signals that help us track satellites in space.<\/p>\n\n\n\n Just above VHF is UHF<\/strong>, or Ultra High Frequency, which covers from 300 MHz up to 3 GHz. You can find UHF in TV broadcasts, mobile phones, GPS devices, and many satellites sending back detailed information.<\/p>\n\n\n\n For small satellites, these two frequency bands each have their own special roles:<\/p>\n\n\n\n What makes these bands great for small satellites is that they don\u2019t need big or complicated antennas to work well. Plus, many amateur radio enthusiasts around the world use these same frequencies, creating a helpful community that supports satellite communications.<\/p>\n\n\n\n Let\u2019s be honest\u2014small satellites don\u2019t have much space inside. Imagine trying to fit all the tools you need into a tiny backpack. That\u2019s what engineers face with antenna size, power supply, and the weight of all the parts.<\/p>\n\n\n\n This is where VHF and UHF come in\u2014they\u2019re like the perfect-sized tools that fit just right. Because their radio waves are longer, they let satellites use:<\/p>\n\n\n\n For example, on HADES\u2011ICM satellite, we used a special soft antenna that can pop out like a spring. It\u2019s light and easy to pack for launch. Once the satellite reached orbit, the antenna unfolded smoothly and quickly started sending out its signals within the first few trips around the Earth.<\/p>\n\n\n\n Communicating in Real Time (Sort Of)<\/strong><\/p>\n\n\n\n Using UHF and VHF radio isn\u2019t about sending super-fast videos or live streams\u2014you won\u2019t be watching HD movies from a PocketQube anytime soon.<\/p>\n\n\n\n Instead, these satellites send little bursts of information called packets. Think of packets like tiny envelopes carrying important updates\u2014things like the satellite\u2019s health, where it is in space (GPS coordinates), sensor readings, and results from experiments onboard.<\/p>\n\n\n\n For example, our HADES\u2011ICM satellite sends out these packets using a format called AX.25\u2014which is a common language many amateur radio operators and satellite enthusiasts use to communicate. Inside these packets, you\u2019ll find important details like battery levels, internal temperatures, system status, and how long the satellite has been operating.<\/p>\n\n\n\n On the ground, stations\u2014both ours and those run by volunteers worldwide\u2014use special radios called Software-Defined Radios (SDRs) to listen and decode these packets in real time. This global network of listeners is what keeps small satellites visible and connected, even when budgets are tight and resources limited.<\/p>\n\n\n\n Remember how we talked about VHF as the satellite\u2019s \u201cbeacon light\u201d that sends simple signals, and UHF as the \u201ctwo-way walkie-talkie\u201d for sending and receiving messages?<\/p>\n\n\n\n Now, let\u2019s look at the strengths and tradeoffs of these two radio types:<\/p>\n\n\n\n VHF (the beacon light):<\/strong><\/p>\n\n\n\n \u00b7 Its signals can travel farther at the same power\u2014like a bright flashlight reaching far into the night.<\/p>\n\n\n\n \u00b7 It doesn\u2019t get weakened much by the air around us.<\/p>\n\n\n\n \u00b7 And it can work with very simple, basic antennas.<\/p>\n\n\n\n But, to get the best signal, VHF antennas tend to be larger\u2014so they take up more space. Also, the VHF frequency band can get crowded, limiting how much data can be sent.<\/p>\n\n\n\n UHF (the two-way walkie-talkie):<\/strong><\/p>\n\n\n\n \u00b7 Has smaller antennas that fit well on tiny satellites.<\/p>\n\n\n\n \u00b7 Can send data faster, which is great for more detailed information.<\/p>\n\n\n\n \u00b7 Works well with flexible radios called Software-Defined Radios (SDRs).<\/p>\n\n\n\n However, UHF needs a bit more power, and because its signals are higher frequency, it\u2019s more sensitive to how the satellite is positioned and pointed.<\/p>\n\n\n\n For our icMercury mission, we chose UHF because it balances simplicity and good performance. Plus, it lets us connect with a vibrant community of amateur satellite listeners\u2014some of our most helpful partners!<\/p>\n\n\n\n Software-Defined Radios: A Game Changer<\/strong><\/p>\n\n\n\n Not long ago, receiving satellite signals required custom hardware. Today, SDRs have transformed the landscape.<\/p>\n\n\n\n We use SDRs both on the ground and in orbit. They allow us to:<\/p>\n\n\n\n It\u2019s like having a radio that can reinvent itself after launch. And when your satellite is already hundreds of kilometers above Earth\u2014far beyond reach\u2014that kind of flexibility becomes incredibly valuable.<\/p>\n\n\n\n A Tool for Global Participation<\/strong><\/p>\n\n\n\n One of the best things about using UHF and VHF frequencies is how easy they are to access. You don\u2019t need expensive, high-tech gear to listen to a small satellite flying overhead. Even a student with a simple antenna, a small radio device called an SDR dongle, and a little patience can tune in and hear signals from space.<\/p>\n\n\n\n We\u2019ve gotten messages from high school clubs in Spain, hobby radio fans in Germany, and teachers in Southeast Asia\u2014all listening and sharing data from PocketQube satellites. That\u2019s the real magic of these frequencies: they open the door to space for everyone.<\/p>\n\n\n\n And when we say we want to make space accessible to all, it\u2019s not just a slogan. This is exactly how it\u2019s happening.<\/p>\n\n\n\n Sharing the Stage Globally<\/strong><\/p>\n\n\n\n This November, Interstellar Communication Holdings Inc. will take part in the 2025 Go Global Awards in London, hosted by the International Trade Council. For us, this is more than just an award\u2014it\u2019s about building connections.<\/p>\n\n\n\n We\u2019re joining a worldwide group of innovators who are opening new paths in technology, science, and communication. And our story is simple: even the smallest satellite, using the simplest radio, can reach people all around the world.<\/p>\n\n\n\n We\u2019re proud and excited to share this message on the global stage.<\/p>\n\n\n\n Final Thoughts<\/strong><\/p>\n\n\n\n In a world full of laser links and high-tech quantum signals, it\u2019s easy to forget about the simple power of UHF and VHF. But these radio waves\u2014quiet, reliable, and well understood\u2014are still the lifeline that keeps small satellites connected all over the world.<\/p>\n\n\n\n They\u2019re more than just tools\u2014they\u2019re open invitations. To listen. To build. To connect. And maybe, that kind of connection is exactly what space needs today.<\/p>\n\n\n\n #UHF #VHF #SmallSatComms #PocketQube #HADESICM #SDR #SatelliteCommunications #AmateurRadio #AX25 #CubeSatCommunity #InterstellarCommunication #GoGlobalAwards #OpenSpaceAccess #icMercury #NewSpace<\/p>\n\n\n\n Disclaimer<\/strong><\/p>\n\n\n\n All satellite communications and frequency usage described in this article are conducted in full compliance with applicable national and international regulations.<\/p>\n\n\n\n Interstellar Communication Holdings Inc. operates exclusively on authorized amateur and\/or educational frequency bands, and any data transmitted from our small satellites\u2014such as beacon packets\u2014are intentionally designed for open, public reception.<\/p>\n\n\n\n We fully respect global spectrum coordination policies and support responsible, transparent use of space technologies.<\/p>\n\n\n\n Mentions of ground-based signal reception by students, educators, and amateur operators refer only to legally permitted activities involving publicly accessible signals. No proprietary or sensitive data is ever transmitted or disclosed.<\/p>\n","protected":false},"excerpt":{"rendered":" There\u2019s a strange beauty in the way satellites communicate. No wires, no internet cables\u2014just invisible waves passing through space. These signals travel across oceans and continents, carrying important information like satellite health, position, and sometimes even voices. For small satellites like PocketQubes\u2014tiny spacecraft that can fit in your hand\u2014the most common way to send and […]<\/p>\n","protected":false},"author":2,"featured_media":436,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","_FSMCFIC_featured_image_caption":"","_FSMCFIC_featured_image_nocaption":"","_FSMCFIC_featured_image_hide":"","_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[1],"tags":[33,28,29,24,34,25,26,32,31],"class_list":["post-435","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized","tag-amateurradio","tag-icmercury","tag-interstellarcommunication","tag-pocketqube","tag-satellitecommunications","tag-sdr","tag-smallsat","tag-uhf","tag-vhf"],"yoast_head":"\n
\n\n\n\nWhat Are UHF and VHF?<\/h3>\n\n\n\n
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\n\n\n\nWhy Small Satellites Use Them<\/h3>\n\n\n\n
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\n\n\n\nUHF vs. VHF: What\u2019s the Difference?<\/h3>\n\n\n\n
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