60GHz frequency bands | 60GHz benefits | 60GHz wavelength, applications
This page describes 60GHz frequency bands, 60GHz wavelength, 60GHz usage or applications, 60GHz benefits and issues or challenges encountered in using 60GHz frequency.
What is 60GHz?
Following are the features of 60GHz frequency.
• This particular frequency falls in millimeter wave range (i.e. 30 GHz to 300 GHz) in the electromagnetic frequency spectrum.
• It falls in globally used unlicensed band viz. 57 to 66 GHz recently adopted across the world for commercial use for wireless communication.
• 60GHz wavelength is about 0.5 centimeters. It is calculated using λ = c/f, where c is speed of light (i.e. 3 x 1010 cm/s) and f is operating frequency.
• It is also known as V-band frequency.
• It is used for low power and short distance communication.
• As shown it occupies 9GHz of bandwidth in the frequency spectrum with four popular channels viz.
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).
• All the channels use about 2 GHz of bandwidth.
• Though it was initially used in military applications due to high security concern, now it is employed in WiGig ( WiFi 802.11-ad ), WirelessHD, wireless PAN etc.
• Physical layers for this frequency has been defined in IEEE 802.15.3c-2009 standards. There are three physical layers for different applications/modes.
Why 60GHz | Benefits of 60 GHz
Following are the benefits of 60GHz frequency. Due to this, it has become very popular in wireless communication.
Initially it was used in military communication due to its high security feature.
➨Sufficient bandwidth of about 9 GHz is used by 60 GHz band (i.e. V band).
➨High EIRP can be used at this frequency.
➨Less likelihood of interference due to low power operation at this frequency. Moreover as low power transmissions can not propagate for longer distances, frequency reuse density can be increased by proper radio frequency planning.
➨Small size of antenna can be realized at this frequency and hence antenna arrays can be developed with smaller sizes with high gains. Massive MIMO systems have been developed due to this feature.
➨Less power and less distance avoids chances of theft and hence it delivers highly secured information transfer over wireless connection.
60GHz usage or applications
Following are the list of 60GHz applications where it is used.
• It is used for development of high rate (> 20 Mbps) WPANs as specified in IEEE 802.15.3-2003 standard.
• The PHY layer specifications have been developed from previous standard (IEEE 802.15.3-2003). The result is IEEE 802.15.3c-2009 standard. This standard specifies three PHY variants viz. SC, HSI, 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 which uses CMOS, InP, SiGe ICs will be used extensively in 60GHz WLAN devices. This is as per IEEE 802.11.ad (2009 - 2012) standard.
Challenges or issues encountered in using 60GHz frequency
Following are the issues which is of concern while using 60GHz frequency.
➨Path loss is more at this frequency. This limits distance coverage at 60 GHz frequency. The high path loss can be mitigated by using higher antenna gains.
➨60 GHz frequency incurs more attenuations through walls, doors etc. which prevents its transmission through such structures.
➨RF absorption peak is substantial at 60 GHz due to resonance of oxygen. This is observed at distances more than 100 meters. For low distance communication this does not have any effect in using 60 GHz frequency.