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As a working group which takes charge of the standardization of the
Next-generation PHS in PHS MoU Group, NWG (Next-generation PHS ad-hoc Working Group) is pushing forward the development
of Next-generation PHS system actively. In March 2007, the Next-generation PHS officially joined ITU-R Recommendation.
The process of that is stated below. In addition, I will introduce the Japanese BWA movement such as candidate systems for
the 2.5GHz band which have been examined in the Telecommunications Council.
Besides, because the Next-generation PHS became one technology of
BWA Recommendation, the articles of Next-generation PHS would be included in other ITU-R documents. I will make some
summary explanations of them and show parts of the publishing article in the second volume that is to appear in the next
mail magazine.
<Next-generation PHS joined ITU-R Recommendation>
For setting the Next-generation PHS into ITU-R Recommendation, many significant processes were necessary, though it was
short for the period. I will introduce some symbolical parts of them.
Official approval of Next-generation PHS standard in PHS MoU Group
Discussion for the standardization of Next-generation PHS was started in 2005 by NWG which was actually a sub-working group
of TWG at that time.
After the official establishment of NWG, more intensified work is
carried out continuously and as the first product of NWG, the Next Generation PHS Standard first edition was officially
approved on the general meeting of PHS MoU Group on Aug. 22, 2006.
Because the official approval and the general release of the standard
are both the prerequisite conditions to join ITU-R Recommendation, we pushed the publishing of a special page for the
Next-generation PHS on PHS MoU Group’s HP site to release the standard impressively.
Next-generation PHS was proposed on ITU-R WP8A Conference
In the March 2006, before the Next-generation PHS standard approval, the Next-generation PHS was firstly introduced at the
ITU-R WP8A Conference held in Geneva Switzerland. At that time, WP8A was working the compilation for BWA Recommendation
and some other systems including WiMax had already been included in the draft document. Because information of
Next-generation PHS was regarded as insufficient at that point since the standard had not approved yet in PHS MoU Group,
WP8A requested to prepare sufficient contents of the standard at the next conference as a necessary condition.
Then, after half a year, at the WP8A conference held in Geneva in
September last year, the information of Next-generation PHS standard, which had been already approved by PHS MoU Group,
was successfully contributed and information of other systems was also added as well, the draft BWA Recommendation was
basically completed.
After the WP8A approval, the draft BWA Recommendation passed the SG8
conference without any difficulties which is the upper ranked conference of WP8A. Then the draft BWA Recommendation
reached to the stage of waiting for the adoption and approval by respective countries by correspondence procedure.
Besides the Next-generation PHS standard, BWA Recommendation includes other standards
such as IEEE802.16e, HiperMan and ATIS WTSC, and also includes systems like IEEE802.11 Wireless LAN and IMT-2000 which
are obscure being regarded as BWA systems.
Now, as the time limit for correspondence procedure has expired in
March 2007, the draft BWA Recommendation has moved into the official ITU-R Recommendation as “Recommendation ITU-R
M. 1801&rdquo.
From now on, the Next-generation PHS will be regarded as one of
the major international standards which was officially recommended by ITU-R as BWA system.
General Appearance of ITU-R Conference
The ITU-R WP8A Conference is usually held at the ITU-headquarter in Geneva, Switzerland. The conference lasts for around two weeks. During the period, respective working groups work on respective schedules without enough breaks from morning to dusk. WP8A holds several plenary meetings at the beginning, in the middle and at the closing date to execute examinations and approvals.
Condition of 2.5GHz Bandwidth in Japan
The Japanese Telecommunications Council has substantially
completed the final report on the technical conditions for candidate systems to be used
in 2.5GHz band. Possible candidate systems are including WiMAX, MBTDD-Wideband,
MBTDD-625kMC and Next-generation PHS. All of 4 systems above have been regarded as
satisfying the conditions which are “the down-link transmission rate of over 20Mbps for
10MHz”, “the up-link transmission rate of over 10Mbps for 10MHz”, “the high spectral efficiency”
It is determined that the guard band between two systems whose TDD timings are synchronized is 1MHz, the guard band between two systems whose TDD timings are not synchronized is 5MHz.
Then, for only Next-generation PHS and WiMAX of 4 systems above, the technical conditions for Fixed Wireless Access (FWA) have also been made. (example: high antenna gain for terminals is over 20dBi)
To be continued to the Second Volume
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