On September 16 (Thu.), 2004, Mr. Osamu Kamimura of DDI POCKET, Inc. (DDI POCKET), gave a lecture on the above theme in the following three sessions.

(1) Cell Planning

[Click the image to enlarge]

     Because that the PHS was based on unprecedented micro-cell system, there were no clear cell design process or standards.
     However, the service area requested for the PHS was quite wide almost as the cellular phones and moreover indoor coverage was also required.
     DDI POCKET repeated trial and error how to establish the service area for such unprecedented micro-cell system and has now got the cell design process based on its past experiences.
     In this session, before introducing the cell design process itself, an explanation on some basic knowledge useful for the cell design was given ("PHS Cell PlanningEtextbook). By acquiring these knowledge to some extent further understanding of the cell design can be expected.
     As such knowledge useful for the cell design, radio wave propagation theory, difference in the cell structure for cellular phones and the PHS, outline of the PHS wireless technology, PHS link budget, type and use of antenna were explained.
     Among those, interference suppression and the use of the polarized wave are directly related to the cell design and should especially be paid attention to. And as for the type and use of antenna, the way based on DDI POCKET know-how to select an antenna was also introduced and this portion would become quite important for the cell design process.
     Further, problems of the CS installation on the rooftop of the building and their solutions were introduced as well.

(2) Cell Station Installation Manual
     DDI POCKET's Cell Station installation manual in use was introduced. This manual has been written based on its past experiences and how to establish the service area is described in each phase.
     As for how to design a new service area, detailed design processes are described by those oriented to outdoor and indoor portion in order.
     Further, as for the design process to expand the existing service area, two cases, one is to increase the radio wave propagation into the room and the other to reinforce the specific spots are described separately. And different cell design process is provided according to each target area, downtown or residential etc.
     The point to be paid attention for actual CS installation location and how to select an antenna are also described as the most important matters.
     This manual could be of much help for establishing a new service area or reviewing the existing service area etc.

Features of Areas      The areas have various features subject to the service to be provided which must be carefully considered in designing a CS installation. This manual classifies these areas as follows, and explains how to design a CS installation by each classification. - Area Configuration Image - [Click the image to enlarge] To establish the service area shown above, the entire area is to be divided as follows and the service area is to be established according to each area's features. *Each area is explained later. [Click the image to enlarge]

Excerpt from the Cell station Installation Manual

(3) Cell Planning - Examples of Solutions -
     Some examples of solutions for the problems found during the cell planning were given. An explanation on "Antenna Replacement" and "Addition of CSs" as a case of such solutions and on "Outline of the Data Monitoring" was given as well.
     Finally, examples of the CS installation by DDI POCKET ware introduced in individual cases such as installation on a building, on a dedicated antenna pole, indoor and on a steel tower.