English हिन्दी
Connect with us

Latest Science News

NavIC frequency too close to WiFi, may cause interference: Study

Published

on

NavIC frequency too close to WiFi, may cause interference: Study

~By Dinesh C Sharma

NavIC, India’s very own navigation satellite system, is projected to provide positioning and navigation services on the lines of US-owned Global Positioning System (GPS). However, a new study has warned that signals from NavIC satellites may interfere with WiFi signals in receivers.

The Indian navigation and positioning system consists of a constellation of seven satellites launched by the Indian Space Research Organisation (ISRO) between 2013 and 2018. The technology is likely to be available on smartphones and car navigation systems in future.

The NavIC satellites send signals in frequency bands of L5 (1176.45 MHz) and S-band (2492.08 MHz).  S-band is utilized by NavIC for navigation systems, but the same band is also shared by other communication systems like Long-Term Evolution (LTE), Bluetooth and Wireless Fidelity (Wi-Fi).

The study says that NavIC signals get affected by  out of band interference due to Wi-Fi signal as the two are located closely. It found that “NavIC reception on S-band frequency is severely affected by Wi-Fi transmission.”

“These interfering signals present a threat to the NavIC receiver performance. To equip both the facilities (WiFi and NavIC) in future cell phones, it will be a challenge to mitigate such kind of radio frequency interference,” says the study published in journal Current Science. The study was done by Dr Shweta N Shah of Electronics Engineering Department at Sardar Vallabhbhai National Institute of Technology, Surat, and Ph D scholar Darshna D Jagiwala. ISRO’s Ahmedabad-based Space Applications Centre (SAC) provided necessary equipment for the study.

Explaining the findings, Dr Shah told India Science Wire that “NavIC has S band signals and there are much stronger terrestrial S band signals that can pose problem for S band and dual frequency Standard Positioning Service (SPS) receivers of NavIC if not addressed properly.”

Currently, she said “Wi-Fi receivers are present in every cell phone. That’s why it was necessary to study Wi-Fi interference to verify the performance of NavIC signal reception in cellphones. This kind of interfering signal represents a threat to the performance of the NavIC receivers.”

In the experimental set up having both types of receivers, it was found that a part of the S-band of NavIC system overlaps the unlicensed band which is shared by other communication technologies like Bluetooth, Wi-Fi and Industrial Scientific Medical (ISM) bands. When the frequency channel of Wi-Fi was superimposed with the frequency of the S-band signal of the NavIC receiver, interference was observed in S-band signal of NavIC receiver due to the extremely low power level of the signal at the user’s receiver.

aaaa

Wireless experts feel radio frequency interference between NavIC and other bands may pose regulatory challenges, besides quality of services. In India, Wi-Fi signals are exempted from licensing in the frequency band 2400 – 2483.5 MHz. This means the usable part of any Wi-Fi system or channel India must be contained within 2483.5 MHz.

“Residual or unintended signals normally go beyond this limit due to the basic characteristic of digital emissions. The NavIC signal is centered at 2492.08 MHz with a bandwidth of ± 8.25 MHz. This means that the lower part of NavIC signal can get interference from residual / unintended signals of Wi-Fi systems. Also, the upper part of the NavIC signal goes beyond 2500 MHz and since the frequency band above 2500 MHz is used for other purposes, NavIC receivers can pick up signals (and receive interference) from such other systems operating above 2500 MHz,” explained Pawan Kumar Garg, former Wireless Advisor, Government of India, while speaking to India Science Wire.

“To reduce interference from Wi-Fi (below 2483.5 MHz) as well as systems operating above 2500 MHz, it is desirable that the NavIC receivers should use reduced bandwidth of ± 7.5 MHz, if possible, and with sharp cut off filters on both ends,” Garg added. (India Science Wire)

Latest Science News

Astronaut Shubhanshu Shukla to meet PM Modi after return from historic space mission

Astronaut Shubhanshu Shukla, who recently returned from the ISS as part of the Axiom-4 mission, will meet PM Modi this evening. Parliament will also hold a special discussion on his historic journey.

Published

on

Subhanshu shukla

Indian astronaut Group Captain Shubhanshu Shukla, the first Indian to visit the International Space Station (ISS), will meet Prime Minister Narendra Modi this evening at his official residence in New Delhi.

PM Modi to host meeting with astronaut

According to officials, the meeting at 7 Lok Kalyan Marg is expected to take place between 5 pm and 5:30 pm. Shukla, who arrived in India on Sunday, will also be part of the National Space Day celebrations scheduled for August 23.

Warm welcome in India

The astronaut was greeted at the airport by his family, Science and Technology Minister Jitendra Singh, Delhi Chief Minister Rekha Gupta, and hundreds of citizens waving the national flag. Shukla had been in the United States for a year, preparing for the Axiom-4 mission, which launched from Florida on June 25 and docked at the ISS the next day. He served as the mission’s pilot.

Emotional note from Shukla

Before his return, Shukla shared an emotional post on Instagram, expressing mixed feelings of leaving his space colleagues while being eager to meet his loved ones and people of India. He also quoted a song from the film Swades, which he had chosen as his anthem on the launch day.

Parliament session on India’s space journey

In honour of Shukla’s mission, the Lok Sabha is holding a special session today to discuss “India’s first astronaut aboard the ISS – critical role of space programme for Viksit Bharat by 2047.” Union minister Kiren Rijiju said the discussion would highlight the importance of India’s space achievements and future goals.

Continue Reading

India News

Shubhanshu Shukla pens emotional note as he returns to India after space mission

Indian astronaut Shubhanshu Shukla penned an emotional Instagram post as he returned to India after his 18-day ISS mission, marking a milestone in India’s space journey.

Published

on

Indian astronaut Group Captain Shubhanshu Shukla has shared an emotional Instagram post as he heads back home after completing his 18-day mission aboard the International Space Station (ISS).

Astronaut reflects on mixed emotions

In his heartfelt message, written from the aircraft, Shukla expressed the whirlwind of emotions he felt while leaving behind his fellow astronauts, who had been his family during the mission. “As I sit on the plane to come back to India, I have a mix of emotions running through my heart. I feel sad leaving a fantastic group of people behind who were my friends and family for the past year during this mission. I am also excited about meeting all my friends, family and everyone in the country for the first time post mission. I guess this is what life is — everything all at once,” he wrote.

Acknowledges support and inspiration

The astronaut thanked everyone for the love and support he received throughout his journey. He also recalled the words of his commander Peggy Whitson, saying, “Goodbyes are hard, but we need to keep moving in life. As my commander Peggy Whitson fondly says, ‘The only constant in spaceflight is change’. I believe that applies to life as well.”

Shukla ended his note with a line from the song Yun Hi Chala Chal from the film Swades, reflecting his spirit of resilience.

Link to India’s space ambitions

Shukla’s return comes at a crucial time as India advances its space programme. Prime Minister Narendra Modi had earlier mentioned that the astronaut would soon return and that he was tasked with documenting his training and ISS stay. This record will serve as a valuable reference for Gaganyaan, India’s first human spaceflight mission.

Over the past year, Shukla trained extensively at NASA, Axiom, and SpaceX facilities. His flight to the ISS as part of the Axiom 4 mission marked a milestone in India’s preparations for future human space exploration.

The Gaganyaan project aims to send Indian astronauts into orbit aboard an indigenous rocket. The government has also outlined plans for a Bharatiya Antariksh Station by 2035 and a crewed mission to the moon by 2040.

Continue Reading

Latest Science News

Shubhanshu Shukla becomes second Indian in space, lifts off for ISS aboard Axiom-4 mission

Group Captain Shubhanshu Shukla becomes the second Indian astronaut to travel to space after four decades, aboard the Axiom-4 mission to the International Space Station.

Published

on

subhanshu shukla

Group Captain Shubhanshu Shukla of the Indian Air Force has etched his name in history as the second Indian astronaut to travel to space. Launching aboard the SpaceX Crew Dragon on the Axiom-4 mission, Shukla began his journey from NASA’s Kennedy Space Center in Florida, from the very launchpad that propelled Neil Armstrong’s Apollo 11 moon mission in 1969.

Four decades after Wing Commander Rakesh Sharma became the first Indian to journey into space in 1984, Shukla’s mission marks a monumental milestone for India’s space ambitions. Speaking ahead of the mission, Shukla expressed the emotional weight of the moment, saying, “I carry with me not just instruments and equipment, but the hopes and dreams of a billion hearts.”

A multinational crew on a scientific journey

Group Captain Shukla is joined by Commander Peggy Whitson from the US, Slawosz Uznanski-Wisniewski from Poland, and Tibor Kapu from Hungary. The four-member crew is on a mission to the International Space Station (ISS), where they are scheduled to arrive after a 28-hour journey and dock around 4:30 pm tomorrow.

The fortnight-long mission includes the execution of 60 scientific experiments, with seven of them designed by Indian researchers. Shukla is also expected to engage in an interaction with a VIP from space during the mission, adding a special human touch to this scientific voyage.

A mission delayed, but not denied

The Axiom-4 launch had faced multiple delays due to unfavorable weather and technical complications. June 25 finally saw the successful launch, marking NASA’s sixth official date announcement for the mission.

Before lift-off, Shukla shared a heartfelt message with his family: “Just wait for me, I’m coming.” The Indian pilot had been under quarantine for over a month in preparation, ensuring he was in optimal health for the journey.

As the spacecraft orbits Earth en route to the ISS, India watches with pride and anticipation, inspired once again by the courage of its space pioneers.

Continue Reading

Trending

© Copyright 2022 APNLIVE.com