Wind-Flex Application scenarios

WIND-FLEX is proposed as an added-value solution for next generation wireless networking, in particular meeting the performance needs of the WPAN and WLAN application areas both in the home and enterprise scenarios. Indeed on one hand, as far as future home networking solutions are concerned, it must be observed that a mono-cluster approach, with a single wireless distribution point covering the entire home area,

is unsuited to the requirements of concurrent multimedia-rich applications. The mono-cluster would be indeed characterized by poor effective throughput per user (shared media) and lack of flexibility with respect to differences among houses/apartments (room, size, wall) and single end-user scenarios. Therefore a multi-cluster approach has to be preferred, with each single cluster covering a limited area and being dedicated to specific functions/need (entertainment, productivity, automation/control), possibly minimizing the time/complexity/costs of installation and use. On the other hand, in the enterprise environment, besides the need for closing the gap between wired and wireless solutions as far as link speed is concerned, the strong demand for security, mobility and ease of resources access and information exchange (e.g. meetings) push toward a high-performing, intrinsically secure and flexible wireless solution.

Therefore the general proposed architecture envisions the presence of multiple electronic devices in an indoor environment (i.e. office, house) which, when provided with a WIND-FLEX radio interface and co-located in the same short-range coverage area (consistent with the multi and application-specific cluster paradigm), can communicate at very high-speed offering, in addition, the attractive possibility of forming automatically a meshed network. Such a self-configuring networking characteristic, which considers also the run-time dynamic assignment of the roles of network elements among devices, represents an additional value when requiring interconnectivity in an infrastructure-less environment (e.g. WPAN at home) while still remaining compatible with infrastructure-based environments such as those typical of WLAN deployment in enterprises (Figure 1).

Among definitely established market trends in the field of communications, and of course valid for wireless connectivity as well, there is the continuous demand for higher effective data transfer rate and throughput per user.

Besides that, from the user point of view there is a clear need for auto-configuring networking as the user does not have the competencies or does not want to be bored by setting up any kind of connectivity procedure. Solving of this user needs represents a market enabler for enterprise ad-hoc connectivity and for home networking.

Pulled by these trends the WIND-FLEX approach has been on one hand to move towards a higher carrier range and on the other to maximize allocation of radio interface functions in the digital domain.

The 17.1-17.3 GHz frequency range, recommended by ETSI [3], has been adopted in order to achieve the required capacity performance at a reasonable front-end cost, thanks to the foreseen evolution of SiGe processes (i.e. QuBic5G). This choice allows to get access to wider bandwidth, to provide high bit rate at same transmitter power on smaller ranges, and exploit propagation characteristics in smaller ranges and higher frequencies in order to achieve higher spatial capacity density and spectral efficiency. Moreover such frequency range provides higher level of capacity, due to the combined effect of smaller cell size and higher frequency re-use, while at the same time easing concerns about security because of the intrinsic limited propagation through walls.

The maximization of radio interface functions in the digital domain allows for the possibility to automatically and dynamically control whole radio interface and react at all layers to guarantee proper communication conditions, despite varying propagation, traffic loading and networking topology conditions. To implement such features, modulation, coding and access schemes and protocols, have been designed in order to allow highly granular flexible variations of their parameters, instantiated by adaptive algorithms and re-configurable sub-systems.

As a general remark it is worth to be observed here that in all wireless application areas there is a common strong need for high security, high speed, long-range, high spatial efficiency, low power and low costs. Given that it is very difficult to achieve all attributes with a single solution, the analysis of conceivable future technical propositions, the recent history of radio solutions (WHITE PAPER INTEL) and the need for user/cluster/application-specific and dedicated systems could push to envisage a trend toward an improvement of all attributes at the expense of the distance, suggesting a future of wireless networking where WPAN and WLAN could collapse/overlap in the 10m range.

The proposed technology, thanks to the 17GHz propagation characteristics which allows channels with wider bandwidth, smaller ranges and good propagation characteristics, definitely overcomes performances of current state-of-the-art WPAN and WLAN technologies working in the 2.4 GHz (i.e. Bluetooth and 802.11b) or the 5GHz range (i.e. 802.11a), both in terms of maximum bit rate (e.g. 802.11a can achieve in its higher profile a maximum air interface bit rate of 72Mbit/s) and capacity offering, due to easier channel reuse and smaller cell sizes. Furthermore it must be observed that the proposed solution leverages the OFDM know-how accumulated in the last years within the wireless industry, offering an attractive potential for a future backward-compatible, scalable and unique baseband chip solution for wireless networking.

As far as design choices are concerned it must be noted that due to the greater bandwidth coherence offered by 17GHz propagation on a short distance (in the order of 4 MHz) an OFDM system with down to 32 sub-carriers could be designed obviously trading lower complexity in OFDM implementation versus overall maximum bit rate, spectral efficiency and sub-carrier allocation/control granularity. The WIND-FLEX choice of 128 carriers, as a matter of fact, is driven by the latter considerations.

As explained, the WIND-FLEX technology has a high potential to be adopted for next generation enterprise wireless networking (for terminal and/or access point connectivity) driven by data speed and spatial efficiency (b/s/m²) and for ad hoc wireless networking in productivity (e.g. fast synchronization and/or data transfer among IT devices) and in entertainment clusters (e.g. audio/video fast streaming between sources and sinks devices,...) both in the home and enterprise scenarios. A shorter-term business opportunity for WIND-FLEX technology can be foreseen in synergy with existing WLAN technologies, by adopting WIND-FLEX as a wireless backbone for standard wireless LANs. Such combined WIND-FLEX/WLAN’s proposition will enable a true "entirely" wireless network coverage of indoor environments, thus providing a much easier, faster to deploy and flexible (distributing capacity according to needs) design and set-up solution, when compared to the current hybrid Ethernet/WLAN’s solution. Annexed to this document a description of this specific WIND-FLEX-based application is reported, along with details of technical proposed solution and relevant simplified WIND-FLEX specifications.

So far, no specific actions took place vs. regulatory organisations to discuss the use of 17 GHz band and/or closer ranges (say +/- 3 GHz) in which WIND-FLEX technology could be applied without any change in its design.

At any rate, the choice to address the 17.1-17.3 GHz frequency band was in line with existing ETSI recommendation ([5]CEPT/T/R 22-06) assigning them for very high speed wireless LAN use on a non-protected and non-interference basis. Besides that, also CEPT/ERC/REC 70-03 [6] recommended, among others options, the use of 17.1-17.3 GHz for short-range wireless connectivity. A contiguous extension of the available 200 MHz in the 17GHz range was recognised by the ITU study group JRG 8A-9B [6], which proposed further 400MHz extensions from 17.3 to 17.7 GHz.

For USA and Japan similar bandwidth are generically allocated for radio communications.

Given the clear need for wireless systems to move to upper carrier frequency ranges in order to offer to high capacity and higher spatial efficiency and the fact that 17GHz allocation does not provide any harmful interference to other wireless systems, it is expected that FCC and global regulatory approval of this band won't be an issue, assuming industry support of such bands.