New MultiDiverse technology from COMSIS ® provides a significant quantum improvement in transmission data rates, range, power efficiency and Quality of Service to IEEE 802.11a standard used in WLAN communications

Paris, France, July 7, 2003 -- COMSIS® has completed a 2 year development of a state of the art, patented technology called MultiDiverseTM using the combination of MIMO (Multiple Input Multiple Output) and Space/Time Diversity technologies. This technology provides for the first time WLAN transmissions with guaranteed QoS while maintaining compatibility with equipments conforming to the current 802.11a standard. The product availability is scheduled in July 2003.

COMSIS® announced today MultiDiverseTM V1.0 technology, a new additive transmission methodology applicable to any wireless standard which significantly improves the performance of the transmission systems. This technology is a disruptive approach to multi-path wireless transmissions using a patented combination of multiple antennas and space/time diversity. Although MultiDiverseTM V1.0 technology is applicable to many transmission systems, it has only been implemented for the present time to the IEEE 802.11a standard.

Current technical status

All WLAN transmission systems currently in use like IEEE 802.11a, b and g are implementing several strategies in order to protect the transmission channels against multi-paths in propagation channels. 802.11b is using spread spectrum, 802.11a and g use OFDM modulation (Orthogonal Frequency Division Modulation). Because of spread spectrum, the b standard in the 2.4 GHz frequency band is data rate limited (11Mb/s theoretical max). Thanks to the use of OFDM the g standard potentially delivers a higher data rate but is limited through interferers coming from other systems like b for example in the same band. The a standard in the 5 GHz frequency band delivers high data rate but the coverage and range is very limited (less than 33 feet). None of these standards can provide QoS without reducing data rate in a drastic way.

On the contrary, MultiDiverseTM V1.0 technology is a new approach of coding/decoding and multiplexing/demultiplexing antenna signals in wireless environment. The emitted signal is coded and multiplexed through multiple antennas (2, 3, 4, ...,8). The receiver takes benefit from the statistical properties of the multi-path signals received on all antennas to successfully decode all the information transmitted in every single path. This way, the efficiency of the transmission is dramatically increased, allowing the channel capacity to be increased by a factor of up to 8 (432 Mb/s in the case of 8*8 antennas) and the Quality of Service by a factor of 64 (diversity order) versus the a standard. In fact, there is no theoretical limit to the number of antennas being used and therefore, there is no theoretical limit to the improvement factor which can be achieved over a standard transmission system. Moreover, using a high order of diversity guarantees QoS at the physical layer. This is a critical point as it prevents the data rate reduction taking place at the MAC layer when the physical layer is suffering from fading or signal drops. This is what is taking place in the case of all 802.11 standards.

Current WLAN IEEE standards provide adequate data rates and area coverage for usual Internet connections like email and Web browsing. Such applications are possible as long as the number of clients connected to the hot spot is limited and the level of interference is moderate. In 2003, the success of Wi-Fi systems into the market place has already demonstrated the limitations inherent to the current standards. For reliable communications in crowded places with a high level of interference or for reliable uninterrupted high data rate transmissions like home video distribution, the current standards are unable to provide the data rate, area coverage and QoS that are mandatory. MultiDiverseTM V1.0 technology provides enough data rate (up to 108 Mb/s with only 2*2 antennas), area coverage in excess of a residential housing and guaranteed QoS to make such applications reliably possible. The improvements associated with MultiDiverseTM V1.0 technology may be used to greatly reduce power consumption instead of improving range and data rate. It is possible to reduce the power to one tenth the power of the 802.11a standard while maintaining the same data rate and the same zone coverage. Such power reduction is opening a whole new range of applications for mobile and ultra portable devices.

COMSIS has developed a software demonstrator implementing this breaking technology.

Leading companies in the Semiconductor and Telecommunication sector worldwide have already shown strong interest for MultiDiverseTM V1.0 technology.

"MultiDiverseTM V1.0 technology brings significant improvements in performance, power consumption and reliability to wireless communications at a very affordable cost. I believe the end users will rapidly adopt the new applications becoming possible like Home Video Distribution" said Philippe Leclair, COMSIS CEO.

COMSIS is a leading Research and Development and Design House Company in the field of Telecommunication Systems. Established in Paris 7 years ago, COMSIS has already developed several Telecom systems for major international Telecom and Semiconductor companies and the French Ministry of Defense. COMSIS has been granted by ANVAR (French Agency for Innovation) the title of Innovative Company and a complementary funding to complete the project.