Room: Room 101, Morrison Gallery, Bldg: Madlyn L Hanes Library (Building D), Penn State Harrisburg, 777 West Harrisburg Pike, Middletown, Pennsylvania, United States, 17507

The Arecibo Observatory first opened in 1963, has been named an IEEE Milestone in Electrical Engineering and Computing in 2001, and has been a marvel in engineering ever since. It has been a monumental instrument for scientific research in the fields of astronomy, planetary radar, ionospheric probing and HF heating modification, and optical probing of the atmosphere. While the science and the discoveries are well known to many, the antenna technology and engineering are equally as impressive as the discoveries. The original concept, by Prof. William Gordon in the Electrical Engineering Department at Cornell University, was for a 1000 foot parabolic dish aiming only at zenith, with no tracking capability for studies of the ionosphere with the newly developed technique of incoherent scatter radar (ISR). Fortunately, knowledge of some on-going research with spherical reflectors was suggested where the feed could be moved to slew the beam. This talk will discuss the unique designs over the years of antenna feeds and associated engineering for frequencies from HF well into the microwaves. Many upgrades occurred during these years and will be described in detail in the ways they have provided significant improvements to the Observatory’s capabilities. Most of the 430 MHz 96 foot line feed antenna broke off and fell through the dish in 2017 during Hurricane Maria. Then in December 2020, the platform fell into the dish destroying large sections of the dish and the equipment in the platform. There is so much more to tell about the engineering at Arecibo that will be the subject of this presentation. Dinner will consist of: - Chicken Bruschetta - Garden Salad - Roasted Garlic Mashed Potatoes - Honey Roasted Carrots - Assorted Dinner Rolls - Brownies Parking for the event is free and is in the parking lot south of the library. See the below map of the PSU Harrisburg for an overview on where the building and parking is located. There is a fee for the entire dinner+presentation event. There is no fee for only attending the presentation. Speaker(s): Jim Breakall, Agenda: Dinner: 6:00 - 7:00 PM Presentation: 7:00 - 8:30 PM Room: Room 101, Morrison Gallery, Bldg: Madlyn L Hanes Library (Building D), Penn State Harrisburg, 777 West Harrisburg Pike, Middletown, Pennsylvania, United States, 17507

Many of us are old enough to remember the world before the Global Positioning System (GPS) existed. In those old days, we would use paper maps, ask people for directions, and use physical landmarks to navigate to where we needed to go. In ancient times, people used celestial bodies such as the sun, moon, and stars for navigation. Today, whether we realize it or not, we all rely on GPS for many aspects of society. Every cell phone has GPS, almost all unmanned systems have GPS. GPS is used by cars, ships, and planes for navigation. We use it to get to where we need to go. Unmanned systems use it to perform their jobs. Commerce and shipping industries rely on it for global material and product distribution. Commerce relies on it for location-based services (all those apps on your phone you use to buy things). GPS is a cornerstone of America's economy. However, there are many environments in which GPS does not perform well. Furthermore, GPS is vulnerable to many types of hostile attacks. It is possible to jam GPS signals. It is possible to spoof (i.e., impersonate) GPS signals. The GPS satellite constellation itself is vulnerable to attack. Global geopolitical tensions and the military capabilities of many other nations means that one day, it is possible that we all wake up and GPS isn't there, or it isn't usable. So what happens then? This talk first presents an overview of the GPS system and how GPS works. The talk then goes on to discuss some of the performance challenges faced by GPS (e.g., performance in dense urban environments). We then we discuss some of the ongoing research being conducted to defeat the threats faced by GPS. We will learn how researchers are working to both detect and defeat hostile attacks. Finally, the tutorial then goes on to discuss the various methods researchers are attempting to provide reliable positioning, navigation, and timing (PNT) in a completely GPS-denied environment using non-GPS methods. Dinner will consist of: - Carved Beef Brisket - Garden Salad - Fingerling Potatoes - Seasonal Vegetable Medley - Assorted Dinner Rolls - Brownies Parking for the event is free and is in the parking lot south of the library. See the below map of the PSU Harrisburg for an overview on where the building and parking is located. There is a fee for the entire dinner+presentation event. There is no fee for only attending the presentation. Speaker(s): Jack Burbank, Agenda: Dinner: 6:00 - 7:00 PM Presentation: 7:00 - 8:30 PM Room: Room 101, Morrison Gallery, Bldg: Madlyn L Hanes Library (Building D), Penn State Harrisburg, 777 West Harrisburg Pike, Middletown, Pennsylvania, United States, 17507