UWB and mmWave Communication Techniques and Systems for Healthcare - Ultra-Wideband and 60 GHz Communications for Biomedical Applications - page 13

Academia, industry and standardization bodies realized an enormous number of
scientific research projects and activities for modelling the wireless channels, spec-
ifying the potential applications and defining communication standards in a way to
integrate this technology as a part in the next-generation heterogeneous networks.
At this point, we must clarify that there are still open research challenges in this
technology from all aspects, beginning with channel modelling and measurements
for the propagation behaviour in different environments, spectrum and carrier allo-
cation techniques, optimal coding and modulation schemes, effective and intelligent
antennas to adaptive and performance-aware DSP capable of supporting different
QoS requirements and service diversity.
60-GHz Standardization
The first try for standardization of higher frequency bands which also affected the
UWB and mmWave radios was 802.16 in 2001 allowing communication links from
2 to 66 GHz. However, the standard was targeting mobile applications and recom-
mendations were to use lower bands which are not unlicensed, most crowded and
expensive for allocation.
To overcome the data rate limitations of 802.11 wireless local area networks
(LANs) which started facing the future usage models with high demand for multi-
media applications, two new IEEE working groups were started: TGac—to specify
extensions of 802.11n with challenge to achieve 1 Gbps (802.11ac at 5-GHz band),
and TGad which in partnership with WiGig (Wireless Gigabit Alliance) have pro-
posed 802.11ad with target to provide up to 7 Gbps by using 2 GHz of the spectrum
at 60 GHz. This standard is expected to arrive in the market in the early days of
2014. 802.11ad is backward compatible with 802.11 management plane including
mechanism for very fast session transfer among 2/5/60-GHz infrastructure networks.
In 2005, TG3c group was founded by IEEE with task to provide mmWave PHY
specification upgrade for IEEE 802.15.3-2003. In 2006, ECMA TC-48 (TC32-TG20)
started the tasks for standardization of PHY and MAC for high data rate 60-GHz mul-
timedia streaming and large data exchange applications. ECMA TC-48 developed the
ECMA 387 specifications for high data rate PHY, MAC and HDMI PAL. Interesting
point is that in ECMA 387 [ 27 ], depending on power constraints and complexity,
three types of devices are defined: Type A, B and C, where Type A are the most
power-consuming/complex while Type C are least complex and power-consuming
devices with lower data rate requirements. The most important goal of this standard
was to provide longer operation time on battery-powered devices by implementing
two power management modes, active and hibernation, with ability of the devices
to select optimal combination of power and transmit rate to reduce BER/FER by
allowing the receiving device to recommend data rate and power level based on QoS
requirements of the service and the sending device may request feedback for the link
quality to finally decide the transmit data rate and power level. Hence, the protocol
complexity has increased, especially for Type A devices where by the specification