Understanding the 60 GHz Frequency Band: Applications and Challenges

Introduction

The 60 GHz frequency band is attracting significant attention due to its distinctive properties that enable high-speed wireless communication and low-latency performance. With applications ranging from WiGig and 5G to advanced radar systems, this unlicensed spectrum is revolutionizing industries, particularly in millimeter-wave applications.

However, alongside its advantages, the 60 GHz band also presents challenges, such as a limited range and susceptibility to environmental factors. This guide explores the applications, benefits, and challenges associated with the 60 GHz frequency band and wavelength to help you understand its role in modern technology.

What is 60 GHz?

The following are key features of the 60 GHz frequency:

• This frequency falls within the millimeter-wave range (30 GHz to 300 GHz) in the electromagnetic spectrum.

• It resides in the globally used unlicensed band (57 GHz to 66 GHz), recently adopted worldwide for commercial wireless communication.

• The 60 GHz wavelength is approximately 0.5 centimeters. This is calculated using the formula:

  $\lambda = \frac{c}{f}$

  where $c$ is the speed of light ($3 \times 10^{10}$ cm/s) and $f$ is the operating frequency.

• It is also known as the V-band frequency.

• It is used for low-power and short-distance communication.

• As shown in the image above, it occupies 9 GHz of bandwidth in the frequency spectrum, featuring four common channels: channel-1 (center frequency: 58.320 GHz), channel-2 (Fc: 60.48 GHz), channel-3 (Fc: 62.64 GHz), and channel-4 (64.80 GHz).
• Each channel utilizes approximately 2 GHz of bandwidth.
• Initially used for military applications due to high-security concerns, it is now employed in WiGig (WiFi 802.11-ad), WirelessHD, wireless PANs, etc.
• Physical layers for this frequency are defined in the IEEE 802.15.3c-2009 standard. There are three physical layers for different applications/modes.

Advantages of 60 GHz Frequency

The 60 GHz frequency offers several benefits, making it very popular in wireless communication. Initially, it was used in military communication due to its high-security features:

• A sufficient bandwidth of about 9 GHz is used by the 60 GHz band (i.e., V band).
• High EIRP (Equivalent Isotropically Radiated Power) can be used at this frequency.
• There is less likelihood of interference due to low-power operation. Moreover, because low-power transmissions cannot propagate over long distances, frequency reuse density can be increased through proper radio frequency planning.
• A small antenna size can be realized at this frequency, enabling the development of antenna arrays with smaller sizes and high gains. Massive MIMO systems have been developed based on this feature.
• Lower power and shorter distances reduce the chances of interception, providing highly secure information transfer over wireless connections.

60 GHz Applications

Following are applications of the 60 GHz wavelength where it is used:

• It is used for the development of high-rate (> 20 Mbps) WPANs, as specified in the IEEE 802.15.3-2003 standard.
• The PHY layer specifications have been developed from the previous standard (IEEE 802.15.3-2003), resulting in the IEEE 802.15.3c-2009 standard. This standard specifies three PHY variants: SC, HSI, and A/V mode.
• WirelessHD 1.0 and 1.1 technology versions.
• ECMA-387 and ISO/IEC 13156 (2008 - present).
• NGmS (Next Generation millimeter-wave Specification), (2007 - 2009).
• Wireless Gigabit Alliance/WiGig (2009 - 2013) technology.
• Chips using CMOS, InP, and SiGe ICs will be used extensively in 60 GHz WLAN devices, as per the IEEE 802.11.ad (2009 - 2012) standard.

Challenges in Using 60 GHz Frequency

The following are concerns associated with using the 60 GHz frequency:

• Path loss is higher at this frequency, which limits the distance coverage. The high path loss can be mitigated by using higher antenna gains.
• The 60 GHz frequency incurs more attenuation through walls, doors, etc., preventing transmission through such structures.
• A significant RF absorption peak occurs at 60 GHz due to the resonance of oxygen, observed at distances greater than 100 meters. This does not have a significant effect on short-distance communication.

Conclusion

The 60 GHz frequency band offers unparalleled potential for high-speed data transfer, low latency, and innovative applications across various sectors. While limitations such as short range and environmental sensitivity present challenges, advancements in technology are gradually addressing these issues. As industries continue to adopt the 60 GHz band, it is poised to drive the future of wireless communication and beyond.