NTT DOCOMO is licensing patents essentialnotice1 to the third-generation (3G) mobile communications system, W-CDMA. Manufacturers interested in obtaining licenses are requested to follow the instructions below.

Please note that in addition to direct licensing, NTT DOCOMO also offers licenses for its W-CDMA essential patents to manufacturers through the (Page will open in a new window.)W-CDMA Patent Poolnotice2 administered by Sipro Lab Telecom Inc..

  • notice1 "Essential patents" are defined as those patents that are necessary for manufacturing products or systems that satisfy the standards of the relevant standardization committees.
  • notice2 "W-CDMA Patent Pool" is a mechanism whereby a plurality of patent holders, including NTT DOCOMO, license their W-CDMA certified essential patents jointly in a single package.
  1. Licensing Terms and Conditions
    Licenses will be granted on a non-exclusive, non-discriminatory basis and on reasonable terms.
  2. Application Process

    To apply for a license, please complete the application form available at the link below and return it by fax. Any inquiries regarding licensing should also be made via the application form. NTT DOCOMO will acknowledge application upon receipt of the application form.

    We will use personal information obtained from your application only for the purpose of completing the licensing procedures and not for any other purpose, and we will not share your personal information with other companies without prior consent.

    The application form should be submitted to:
    Fax: +81-3-5156-0233

  3. W-CDMA Essential Patent License Inquiry/Application Form

    (Open a PDF file)Application form for the license of W-CDMA essential patents (PDF format: 8KB)

  4. List of Essential Patents
    Please refer to (Page will open in a new window.)Association of Radio Industries and Businesses (ARIB) and the (Page will open in a new window.)Telecommunication Technology Committee (TTC) (in Japanese only).

FOMA Technology

NTT DOCOMO's 3G FOMA service, deployed in the 2 GHz frequency band, uses packet data transfer speeds ranging from 64 kbps to 384 kbps to support a broad variety of applications that include Internet access, e-mail, file transfers, remote log-in and Internet phone applications. In addition, ISDN-type services functioning on a streamed basis effectively employ nx64 kbps channels to support applications such as telephony, video-conferencing and Group 4 faxing. Further, high-quality voice services at up to 12.2 kbps are also available. These cutting-edge services are supported by the following technologies.

Network technology

NTT DOCOMO's 3G network uses an architecture completely different from 1G and 2G. Employment of ATM technology manages packet and circuit switching on the same network node, allowing use of various traffic types for true multimedia capability. Asymmetric communications with different characteristics for up- and down-link are also made possible by ATM's ability to handle these resources separately. Additionally, ATM allows flexible connection services such as point-to-point and point-to-multi-point connections.

Image of Merits of Applying ATM

Intelligent Networks (IN) are in telecommunications use worldwide and the introduction of 3G service in Japan has greatly enhanced them, not least by providing quicker response to customer needs. What's more, development costs are lower and more easily controlled, while Global Roaming (Virtual Home Environment) has become a practical possibility.

Image of Intelligent Network

W-CDMA technology

Two innovative technologies employed in W-CDMA are key to FOMA's unmatched ability to handle a wide range of content including sound, video and still images:

  • Spread Spectrum technology
    that employs a wider frequency band to transmit radio signals.
  • Multirate technology
    that selects speed and transmission channel based on data type and size.

Spread spectrum method

High-quality, high-efficiency transmission

W-CDMA spreads signals over a frequency range several hundred times broader than conventional system's, and allocates single time slots to each user. Since this method allows all users to share the broad bandwidth, splitting the bandwidth becomes unnecessary and transmission efficiency is vastly improved. In addition, spread spectrum is highly resistant to disturbance and noise, and the use of a common frequency in all cells minimizes jamming and interference. The need for frequency-switching when a user moves from one station's coverage to another is eliminated to make high-quality communications possible.

Image of Principle of W-CDMA

Multirate transmission method

Efficient, high-speed processing of various data types

Critical to the success of FOMA is W-CDMA's ability to handle the system's massive data content. This is achieved through the use of multirate transmission that automatically selects the optimal transmission speed and route according to data type and size, to assure high-speed high-quality handling of content including voice, still images and video.

Image of Principle of W-CDMA Multirate Method

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