All Blogs By John Fischer

 
By John Fischer, VP, Advanced R&D
 
Cybersecurity is a hot topic today. Hackers are always looking to undermine our network connections and we are always trying to protect against them. I’m no cybersecurity expert, but I am often asked, “Can Resilient PNT be used to improve cybersecurity?” Resoundingly, “yes.” Here are a few simple examples.
By John Fischer, VP, Advanced R&D
 
Whether in the air, on land, or at sea, vehicles will impart shocks and vibrations to their electronics, sometimes severely. In high vibration environments, the system designer must account for induced phase noise which can drastically affect overall performance. This white paper discusses the challenges of keeping low noise signals pure in any environment.
By John Fischer, VP, Advanced R&D
 
As is widely understood, GPS signals are weak and vulnerable to interference. Interference can be unintentional, such as side band energy from radio transmissions on the battlefield, or intentional. Intentional interference can be jamming or it can be a fake signal, sometimes called spoofing or sophisticated jamming. Spoofing is potentially the most dangerous type of interference. Connectivity and signal disruption is one issue; acting on misinformation or falsified data could be catastrophic.
By John Fischer, VP, Advanced R&D
 
Today's time sensitive networks rely on available and accurate positioning, navigation and timing (PNT) signals to provide leaders with the information required to make timely and effective decisions. The proliferation of GNSS-degrading and denying devices across state and non-state actors put this critical information capability in jeopardy. Learn how a combination of alternative PNT signals with traditional GNSS references makes PNT applications resilient against jamming and spoofing.
By John Fischer, VP, Advanced R&D
 
While the use of GNSS – more commonly known as GPS – is now widespread, the signal itself comes from satellites that are 20,000 kilometers away, making it fairly weak and subject to loss of signal or interference. For military operations, this presents several challenges. In a recent naval exercise, a scenario of GPS denial triggered up to 48 shipboard systems to generate alerts when GPS was lost. This shows how GPS is so pervasive and deeply integrated into many military systems for air, land and sea.
By John Fischer, VP, Advanced R&D
 
A customer with a major datacenter facility was experiencing issues with its GNSS based timing systems. We demonstrate how they overcame interference using a low-cost anti-jam (AJ) antenna.
By John Fischer, VP, Advanced R&D
 
Spectracom has introduced a new Anti-Jam (AJ) antenna for its GNSS-based timing systems that combats interference by limiting the antenna’s reception near the horizon. The antenna’s beam is focused at the zenith – where most of the GNSS satellites are – and away from the horizon, where most interference comes from.
By John Fischer, VP, Advanced R&D
 

The increasing reliance on GNSS signals for positioning, navigation and timing applications across different industries has raised questions about GNSS vulnerabilities and how to address them. We sat down with John Fischer, Spectracom’s chief technology officer, to talk to him about Resilient PNT (also known as Assured PNT and Alternative PNT) and its implications for today’s GPS/GNSS systems.  This continues from Part 1 of John Fischer's Resilient PNT FAQ.

By John Fischer, VP, Advanced R&D
 

The increasing reliance on GNSS signals for positioning, navigation and timing applications across different industries has raised questions about GNSS vulnerabilities and how to address them. We sat down with John Fischer, Spectracom’s chief technology officer, to talk to him about Resilient PNT (also known as Assured PNT and Alternative PNT) and its implications for today’s GPS/GNSS systems.