Current Issue : May - June 2022
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Articles May-Jun 2022

PALM AV-ICN Exhibitor ListingNew!

Exhibitor Listing

Exhibitors spent three fruitful days at the PALM AV-ICN 2022, showcasing latest products and solutions. Browse through the list of all 2022 PALM AV-ICN exhibitors. Exhibitor information is provided solely for the use of attendees to search for brands /products / services offered by exhibiting companies.... read more

Articles May-Jun 2022

TOP 50 PRODUCTS & TECHNOLOGYNew!

Global Pro Sound & Light Technology
TOP 50 PRODUCTS & TECHNOLOGY

PALM has selected the Top 50 Pro Audio and Lighting Products & Technology, trending in the National and / or international markets. The demand for advanced technology has made the industry competitive with global brands unveiling the latest product technology and new versions of equipment with upgraded ... read more

Articles May-Jun 2022

OUTSTANDING CONTRIBUTION TO THE PRO AUDIO INDUSTRYNew!

Glimpse of One of The Plants at Noida, U.P.

This year PALM + AV-ICN is honouring the AHUJA FAMILY for their Leadership of over Eight Decades in the Pro Audio Industry with the Lifetime Contribution to The Pro Audio Industry Award at the PALM Sound & Light awards. This award recognizes over Eighty Years of innovation, quality & reliability of brand AHUJA in meeting the demands of Pro Audio products in India. This award acknowledges their commitment to... read more

Articles May-Jun 2022

AV ARCHITECT OF THE YEARNew!

Awarded for highest standards in adopting best innovation and vision in AV Architecture This award has been instituted for an AV Architect chosen by AV-ICN platform to be recognized for the quality of his body of work, incorporating the best innovation and vision in AV architecture. In this feature, we highlight one of the most prestigious projects accomplished by Narendra Naidu - The Statue of Unity... read more

Articles Mar-Apr 2022

PALM AV-ICN 2022 SHOW PREVIEWNew!

PALM Expo was launched in 2001, in response to the top music recording engineers in Bombay desiring a dedicated pro audio expo. Bombay was the music recording capital and Bollywood Bombay boasted of the big studios and big sound rental companies and the beginning of the big stage... read more

Articles Mar-Apr 2022

Milind Raorane Sets the Tone at ToyRoom MumbaiNew!

ToyRoom outfitted its second outpost in Mumbai with Electro-Acoustic Design Consultant Milind Raorane to deploy a comprehensive Sound and Audio design that would enhance the unapparelled ambience of the nightclub. PALM +AV-ICN Reports.
Nex Protection Technology

Located in Kalina, Mumbai, Toy-Room Mumbai is established on the premises of the vibrant and stylish Grand Hyatt, one of Mumbai's sophisticated leisure and business... read more

Articles Mar-Apr 2022

Post Pandemic Video Conferencing RiseNew!

Abdul Waheed is the Managing Director at EYTE Technologies. A CTS holder from Avixa, Member of the Certificate Committee of AVIXA, has been in the AV industry for more than two decades, delivering many successful projects across various segments. Abdul gives his overview of the video-conferencing industry and the latest market trends.

ommunication, the human connection is the key to personal and professional success. It is very important to have effective communication... read more

Articles Mar-Apr 2022

The CHORDFATHER Experience New!

Neumann's first Studio Monitor Experience Center in Mumbai
Nex Protection Technology

Recently Neumann in collaboration with well-known music composer, producer, sound engineer, and live engineer, Sunny M.R.'s Chordfather Productions announced the launch of its exclusive Studio Monitor Experience Center for audio professionals... read more

Articles Jan-Feb 2022

Understanding the Dynamic Evolution of Projection Technology with NEC New!

Humans have always wanted to bring their imagination to life. Introducing 2K / 4K projectors that deliver superior colors’ and high resolution has made that possible.
Nex Protection Technology

The high detail, true color rendition and cinema-like quality video of projectors are being leveraged by Artists, museums, schools and businesses alike to educate, attract and engage customers or to uplift and inspire people in new and innovative ways...... read more

Articles Jan-Feb 2022

Integrated System Design Crafts a Savvy Aural Experience Hot!

HARMAN Professional Solutions & ISD install a comprehensive Aural setup at Pass Code Hospitality newly opened restaurants.
Integrated System Design

When Pass Code Hospitality opened three new bustling restaurants in Lower Parel, Mumbai, they reached out to HARMAN Professional Solutions and Integrated System Design to deploy a comprehensive Aural setup that enhanced each restaurant's theme well....... read more

Articles Jan-Feb 2022

Star Dimensions India accomplishes STATE-OF-THE-ART- LIGHTING ARCHITECTURE for the "BANDRA WONDERLAND" project in Mumbai New!

Ashish Mehta & Becket Tundatil Creatively Execute Seamless Architectural Lighting Design at the Iconic Bandra-Worli Sea Link.
Bandra-Worli Sea

Between 24th December 2021 and 2nd January 2022, the project came alive as the sun set on the city - with the entire 1.5 km of the Bandra Reclamation promenade being engulfed in specially themed displays that emphasized the four different seasons of the year, boasting different eye-catching..... read more

Articles Jan-Feb 2022

Understanding the Pro-Audio Market with Sennheiser New!

Sennheiser is a leading manufacturer of headphones, loudspeakers, microphones, and wireless transmission systems and has been creating unique sound experiences for customers. PALM+ AV-ICN got in touch with Vipin Pungalia, Director, Sales - Pro Audio & Country Manager, Sennheiser - India, to learn more about the company's plans for the Indian market.
Vipin Pungalia Pro Audio Country Manager Sennheiser

The live music industry had seen a boom before the third wave of COVID stuck. What are the current industry sentiments, and do you think that the industry is poised to see a boom again? India has always been a music-loving country, for global as well as local artists..... read more


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Wave Propagation & Antennas

RF gain can only be obtained through Antenna design, no matter what book you read or what RF course you went for this is an undisputed fact. Antenna is a natural organic part of an insect’s body that we humans have adapted in order to transmit Electromagnetic waves.

Electromagnetic Waves: Now I find Electromagnetic rays very fascinating because these two oscillating fields an electric field and a magnetic field have a relationship that’s always 90 degrees apart, unlike acoustic waves that need a medium to travel, EM (Electromagnetic) rays can even travel in ‘ether’ or we earthlings call vacuum at a propagation velocity of the speed of light. No this is not jargon or rocket science, you would have probably learnt about it in high school/college at an elementary level, not knowing the importance of EM in your everyday professional life.

Wave Equation & Losses of EM: The higher the frequency the shorter the wavelength and a standard RF frequency for entertainment RF is around 600Mhz which equates to around 2 Feet, now here is how the wave propagation can get effected that if an object is 2 feet of bigger in the ‘line of sight’ between the transmitting antenna and receiving antenna there will be surely drop-outs not forgetting that a human body that’s primary composition is of salt-water is a large absorber of the of RF energy and averagely reduces the signal strength by 6db (that’s a lot). Interestingly the more the fat in a humans body the greater the loss and this ends about here before I am accused of ‘body shaming’ but if you are facing RF problems and everyone else isn’t probably its time to check your waistline. Love handles don’t do well with RF.

EM also is subjected to ‘inverse square law as soon as it begins radiating into the environment whether is air or free space and metallic objects in its path too cause havoc in the propagation of the waves this is enough to cause an RF shadow and degradation of the waves.

Polarization Of Waves: Polarization is the electric field orientation of an EM wave. A vertically polarized EM wave is produced when the transmitting antenna is perpendicular to the earth and vice versa. The receiving antenna will get the maximum reception if the transmit antenna has the same polarization and if the transmit and receive antenna are orthogonal/90 degrees apart then the losses can be as low as 20db.

Polarization losses are in addition to the environmental and propagation losses cumulative effect is often referred to as ‘Fade’.

Modulation: Modulation is the process of superimposition the information we wish to transmit (in this case audio) on a high frequency carrier for the purpose of efficient wireless transmission. For example an IEM system, the transmitter takes an audio input signal, modulates this onto a high frequency carrier, then via the antenna, radiates the signal as an Electromagnetic wave. The opposite process occurs at the belt- pack receiver; the high frequency Electromagnetic wave is detected by the receive antenna and is demodulated to recover the original audio signal. There are a multitude of modulation schemes available, both analog and digital.

And Now Antennas: Most audio engineers are aware that it is best practice to maintain a clear line of sight between transmit and receive antennas whenever possible; however, there is sometimes confusion regarding what a clear line of sight actually is. A clear line of sight does not just mean the antennas are visible. The electromagnetic wave should be able to propagate from transmit to receive antenna without interference from obstacles. Transparent materials such as glass, Perspex and water should be considered obstacles, as should seemingly transparent structures such as chain link fences and cages. In entertainment audio, helical antennas have been extremely successful as the orientation of the entertainers bodypack or handheld can keep changing and do not adhere to the transmitting and receiving antennas orientation for maximum reception, so the moment the EM wave enters the helical antenna it gets circular polarized and directional as well thus being able to provide effective transmission and reception.

The standard LPDA (Log Periodic Dipole Antenna) a.k.a ‘fish plate’ antenna too used in most productions effectively do their job well to in indoor applications and in studios where you can mount antennas overhead even omnidirectional do an amazing job. Using the general whip antenna are passé’ and expecting to put on a robust RF environment with them is as good as putting the production on peril.

Diversity: In most wireless microphone applications, even small signal dropouts are unacceptable. Multi-path fading typically causes dropouts, rather than weak signal strength caused by too great an operating distance. One method to reduce the likelihood of dropouts is to use a diversity receiver with two antennas. While it is common practice to connect two physically separated antennas to these inputs, there are other antenna designs that achieve the same goal of reducing dropouts.

The Diversity Fin is my personal favourite and a proprietary and innovative antenna design for entertainment production wireless that statistically eliminates the leading cause of dropouts in low-power wireless applications—multi-path interference. Incorporating orthogonally (perpendicular) opposed elements, a single antenna unit can now provide both cross polarization sensitivity and dual feeds for diversity wireless microphone receivers without the need to deploy two physical antennas at a calculated or estimated distance.

If you look at the Azimuth of the Diversity Fin, one antenna is a Log Periodic Dipole Array giving you a good forward gain with high sensitivity and ignoring unwanted information in the rear. Whilst the dipole has a somewhat omnidirectional unity gain and providing reception to signals that have a polarization above 45 degrees that greatly reduces dropouts due to cross-polarization.

Antenna Location & Distance Between Them: In terms of location, receive antennas should not be positioned closer than one wavelength to any reflecting surface. The RF signal detected by the receive antenna is a complex mix of direct and reflected waves, the nature of which is constantly varying as the transmitter moves. Positioning antennas less than one wavelength from reflective surfaces can increase the risk of a dropout due to reflection induced multi-path phase cancellation. Sometimes environmental circumstances dictate antenna positioning and recommendations such as this cannot be adhered to. In these cases, it usually only takes a minor adjustment to antenna location to completely change the system response, so experiment with positioning to achieve best results.

Another common point of confusion relates to the distance at which antennas should be placed apart. For effective diversity performance, antennas should not be positioned less than 1⁄4 wavelength apart, and ideally, they would be placed 1⁄2 to one full wavelength apart. Diversity systems work best if receive antennas are positioned close enough to exist in the same field of RF reflections, but far enough apart that a multipath drop out condition at one antenna is unlikely to simultaneously exist at the other.

RF Boosters, Filters & Accessories: A lot of people think that the name means adding gain however these electronic boosters are merely used to compensate the cable losses, they can never be thought of boosters for antenna gain, that’s simply a misnomer. RF filters are often used to eliminate spectrum into the receiver front end that’s of no use to it other than adding unwanted noise and intermodulation and such practices are never used in India because merely they aren’t known of or available of the shelves. Trajectory of the antenna comes from good positioning and the use of stands and clamps to achieve line of sight is the key to success, however sometimes you do not want it too high as it unnecessarily increases cable length.

Conclusion

Now this is why such a simple practice is so complex because application engineering is very weak and even if anyone has good knowledge he ends up getting absorbed by the manufacturer, which leads me to tell you why we do not have a single RF tech in India, so why hasn’t anyone wanted to pursue a career in RF Engineering, you in all likelihood will have the busiest job in the audio industry in time to come when the spectrum becomes smaller.


Current Issue : May - June 2022
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