Last years have
witnessed a recent strong interest in cognitive radio technical standardization. For instance, we find the IEEE 802.22, IEEE
802.11af and IEEE 802.19.1. IEEE 802.22 aims at deploying
Wireless Regional Area Network (WRAN) infrastructures in rural and remote areas; this standard is able to attain an aggregate data rate of up to 23 Mbps. It is the most mature cognitive radio standard at this time since it has started the process of standardization in October 2004. The IEEE 802.11af task group is the IEEE standard working on the issue of providing WIFI services over TV bands to achieve higher throughput data rates and faster connections, this task group was formed during December 2009. While using a certain band of spectrum, the secondary system must not only avoid disturbing and interfering with the corresponding primary user but also obtaining awareness about other coexisting secondary systems. Therefore, standards like IEEE 802.19.1 have been proposed to address the coexistence issue between several secondary technologies operating over TV bands. This project was approved on December 2009. The ECMA-392 standard tackles the MAC and PHY parts to enable the operation of portable devices over TVWS, it was published bye the end of 2009. IEEE has recently (September 2011) launched the task group IEEE 802.15.4m (802.15.4 over TVWS) with the goal of enabling WPAN infrastructures over TV bands.
Wireless Regional Area Network (WRAN) infrastructures in rural and remote areas; this standard is able to attain an aggregate data rate of up to 23 Mbps. It is the most mature cognitive radio standard at this time since it has started the process of standardization in October 2004. The IEEE 802.11af task group is the IEEE standard working on the issue of providing WIFI services over TV bands to achieve higher throughput data rates and faster connections, this task group was formed during December 2009. While using a certain band of spectrum, the secondary system must not only avoid disturbing and interfering with the corresponding primary user but also obtaining awareness about other coexisting secondary systems. Therefore, standards like IEEE 802.19.1 have been proposed to address the coexistence issue between several secondary technologies operating over TV bands. This project was approved on December 2009. The ECMA-392 standard tackles the MAC and PHY parts to enable the operation of portable devices over TVWS, it was published bye the end of 2009. IEEE has recently (September 2011) launched the task group IEEE 802.15.4m (802.15.4 over TVWS) with the goal of enabling WPAN infrastructures over TV bands.
All the aforementioned standards are operating
over TV white spaces (54 to 60 MHz, TV channel 2; 76 to 88 MHz, TV channels 5
and 6; 174 to 216 MHz, TV channels 7 to 13; 470 to 608 MHz, TV channels 14 to
36; and 614 to 698 MHz, TV channels 38 to 51). The basic idea behind that is
that the transition of TV channels from analog to digital has freed up a
considerable amount of unused portions of spectrum. It is commonly known that TV
bands have good propagation conditions, excellent building penetration and high
spectrum efficiency. To my best knowledge, there are no other frequency bands
attracting a similar interest.
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