As we see in 3GPP standards, ITU also recommends that the 2.6GHz band to split into a mix of paired spectrum [FDD, Frequency Division Duplex] - in which separate range of frequency are to be allocated for uplink and downlink channels - and unpaired spectrum (TDD, Time Division Duplex) where they use a single range to have up and down timeslots. Most of the regulators (most notably, OfCom) are adopting "technology neutrality" for allocating the spectrum. Technologies like WiMAX, 3G and IT's evolutions such as HSPA or future LTE can have their own path in this 2.6 GHz band. According to the international best practices, and also ITU recommended on having 2.500-2.570 GHz and2.620-2.690 to be used as paired bands for FDD mode and 2.570-2.690 to be used as unpaired band in the middle for TDD mode. In WRC-2000, ITU also suggested two more options for this extension band in 2.6 GHz, one starts with FDD channeling and other TDD channeling in the middle, as discussed. The last option suggested that the regulator should leave that option open to the individual operators to decide on any of these. Can that be left open to the operators?
Intel being the driving force of WiMAX ecosystem wants to see WiMAX and LTE to coexist. Intel strategist Maloney says that two standards should be harmonized because they are about "80 percent" similar but that WiMAX is a couple years ahead of LTE. He also said that customers will be confused by the competing 4G technologies. Maloney says that Intel is looking into ways to integrate the two technologies and it is technically possible for Intel to create a chip set that could be used for WiMAX and LTE. I need some fresh air ...
In the setting of CEPT 70-50-70MHz (FDD-TDD-FDD) band plan, the enlightened regulator might sets this up ... like 60-(50+10)-60-(10) allocation, or 50-(50+20)-50-20, where more WiMAX-suitable spectrum can be kept in the middle and end of the band with 120 MHz duplexing for LTE evolution. Will that be confusing? I guess, 2.3 and 3.4 GHz are natural TDD band. What is the prospect of FDD in 2.6 GHz band? The service providers might get the license for 15 years, what if they choose to offer more voice friendly applications (FDD) after 5 years, should they be able to use the spectrum if they are allowed to trade?
What should the regulators do? Should they specify this 2.6 GHz band to operate only in TDD mode or should they leave it open? What about WiMAX profiling on FDD? What WiMAX forum thinks about FDD?
Thanks in advance.
-- Raqueeb Hassan