A new draft wireless networking standard, a compromise proposal from TI, Intersil and several other companies, offers compatibility with 802.11b and a set of data-rates up to 54Mbps in the 2.4GHz band.
In addition, the new draft standard also contains modes of operation using PBCC-22 and CCK-OFDM (Complementary Code Keying-Orthogonal Frequency Division Multiplexing). This integration of modes will enable consumer products to support multiple modulations and provides a clear bridge from 11Mbps to 54Mbps data rates.
‘The IEEE has defined a clear path for 802.11g that bridges 11, 22 and 54 Mbps, making multi-mode products based on one standard a reality,’ said Allen Nogee, senior analyst Cahners In-Stat/MRD.
‘By already offering 22Mbps capabilities with the ACX100, TI and its customers are well positioned to enable the first step in the deployment of 802.11g compliant products in the 2.4GHz band.’
The 802.11g draft standard uses the framework from the original proposals for 802.11g which called for OFDM in the 2.4GHz band as an optional mode to the primary proposed modulation, either PBCC-22 or CCK-OFDM. The 802.11g draft standard has two mandatory modes, OFDM offering 802.11a data rates in the 2.4GHz band, and implementation of 802.11b CCK for full backward compatibility.
It also offers two optional modes of PBCC-22 and CCK-OFDM, to support rates up to 24Mbps.
‘TI supports the new IEEE 802.11g draft standard and commends the group for its work to reach a well-balanced compromise that offers the WLAN industry a clear path to support multiple modes within a single standard,’ said Marc Cetto, general manager Wireless Networking at TI. ‘This is a positive development for customers offering or developing products based on TI’s ACX100 solution providing 802.11b compliance with differentiating extended data rates via PBCC-22 now, and be confident that their solutions are fully embraced by the 802.11 standards organisation.’
Now that the technology behind 802.11g has been clarified, TI will be developing 802.11g-compliant devices by using elements of its existing 802.11b solution, as well as its 802.11a work in progress, for availability in mid-2002.
Additionally, since TI’s PBCC-22 is specified in the 802.11g draft, the company’s existing devices, which already offer this higher rate feature, will be able to interoperate at 22Mbps with the company’s 802.11g-compliant devices that will also offer PBCC-22. This ensures a high degree of forward-compatible interoperability at this higher data rate, while maintaining full 802.11b compliance.
TI is currently shipping the ACX100 to customers offering 802.11b compatibility with 802.11g standards compliant 22Mbps extended data rates.
For its part, Intersil also announced its support of the new proposal.
‘This is a huge win for the wireless industry for several reasons,’ said Gregory Williams, president and CEO of Intersil Corporation. ‘First, it is backwards compatible with the large installed user base of over 11 million Wi-Fi products. Second, it meets our customers’ demands for significant speed increases in the 2.4 GHz band, necessary for multi-channel DVD-quality video and CD-quality audio applications.’
Intersil will develop and market a new chip set that meets the proposed 802.11g standard by the second quarter of 2002.
The new chip set will implement the proposal’s mandatory CCK and OFDM modulation schemes, supporting data rates up to 54 Mbps.
Intersil, however, will not develop chip sets with the optional CCK-PBCC modulation.
‘We feel that the mandatory elements of the proposed standard meet all the needs of the market,’ Williams commented.