A homegrown trunking communications standard in China, PDT provides a future-oriented digital two-way radio technology to serve the needs of most users in the trunking communications industry. The PDT standard has drawn upon advanced technologies worldwide, such as Tetra, P25, DMR, and MPT1327, and provides an innovative design. The standard incorporates features, such as high performance ratio, security, macro cell, scalability and backward compatibility to combine capabilities of disparate emergency communications networks.

http://www.tetramou.com

The TETRA Memorandum of Understanding (MoU) is an alliance that comprises leading TETRA manufacturers, such as Motorola, EADS, Sepura, R&S, Teltronic, and Hytera. There are over 100 members in the industry chain. 
 
1. Market Positioning (Applicable Industries)
The TETRA Standard targets users in industries such as emergency communications, government and public security, transportation, and public utilities. 

 2. Global Distribution
The TETRA Standard is mainly used in Europe. According to latest statistics from TETRA MoU, the Standard has been accepted by 117 countries and regions, except for North America. 

 3. Technologies and Applications
Based on the 4-time slot time division multiple address (TDMA) technology, the TETRA I standard features a 25 kHz channel internal and a data transmission rate of up to 36 KB/s, and provides a rich set of functions. The TETRA Standard has entered the second stage of development. In the first stage, the Tetra I Standard focuses on voice services and the technology is mature. In the second stage, Tetra II (TETRA enhanced data service (TEDS)) extends reach to high-speed data services. Motorola and Sepura launched a prototype in 2010.

The TETRA digital trunking communications system can provide command and dispatching, data transmission, and telephony services on the same platform. In addition to multi-group dispatching, the system delivers short data information, group data, and digital full-duplex mobile call services. The system also supports powerful direct mode operation (DMO) for mobile stations to provide capabilities such as authentication, air interface and end-to-end encryption. The trunking system includes virtual private networking capabilities to serve a number of independent organizations over one physical network. This system supports a wide range of new applications, such as vehicle positioning, image transmission, mobile internet, and database inquiry.

Operating on cells, the TETRA system is suitable for users that are exposed to high terminal density and complex dispatching, and require powerful data services.

www.dmrassociation.org

As an open standard, the digital trunking communications standard for digital mobile radio (DMR) is designed and formulated by ETSI to target low-end and mid-range specialized and commercial users in Europe. It emerged in April 2005 as a standard for digital mobile wireless communications. The latest version became available in December 2007.

The DMR Association comprises DMR manufacturers, such as Motorola, Hytera, Selex, and Tait.

Members of the association include Aeroflex, CML, Democom, Funkwerk Koelleda, Fylde, Hytera, ICOM, KENWOOD, MOTOROLA, Radio Activity, Team Simoco, SELEX, Tait, Vertex, and Professioneller Mobilfunk.

For more information, visit   http://www.dmrassociation.org/About-the-DMR-Association.htm

1. Market Positioning (Applicable Industries)
The DMR standard is designed for low-end and mid–range specialized and commercial users in sectors such as public utilities, schools, hospitals, hotels, and real estate.

2. Main Features
Operating in operates in the TDMA (double time slots) multiple address mode, the DMR standard provides a channel interval of 12.5 kHz, 4-FSK modulation, and a data transmission rate of 9.6 KB/s. This standard is evolving in three stages: a digital standard for free frequency bands, conventional digital technology and trunking technology.

The DMR standard can fully utilize spectrum resources. Working in macro cell networking mode, the technology supports smooth evolution from analog MPT1327 to digital trunking. The standard provides a wide range of services, strong scalability and backward compatibility. Mover, the technology allows for low-cost systems and terminals and supports swift network construction and cost-effective operation and maintenance (O&M).

www.dpmr-mou.org/ 

Formerly known as Trans European Trunked Radio, TETRA is currently referred to as Terrestrial Trunked Radio. Formulated by European Telecommunications Standards Institute (ETSI), the open standard is designed to meet the requirements of specialized sectors in European countries on mobile communications. Available for use in 1988, it has become a European standard.

The digital private mobile radio (dPMR) describes a digital two-way radio standard released by the ETSI organization. The standard suits commercial, specialized, and public security applications. Based on 6.25 kHz FDMA technology and 4-FSK modulation mode, the dPMR supports data transmission rates of up to 4.8 KB/s. NXDN and DCR are built on the dPMR standard.

Established in 2007, the dPMR MoU is a global organization that comprises manufactures, suppliers, terminal users and testing agencies accepting and promoting the FDMA digital technology. Its leading 12 members include ICOM, KENWOOD, and Hytera.

Currently, the dPMR standard family consists of ETSI TS 102 490 (Tier1) and ETSI TS 102 658 (Tier2).

By using the FDMA technology, the dPMR standard provides a cost-effective digital voice and data solution. By effectively shortening the channel interval through a combination of 6.25 kHz FDMA and 4-FSK modulation technologies, the ETSI dPMR has improved the spectrum utilization efficiency.

NXDN indicates a digital two-way radio standard jointly formulated by KENWOOD and ICOM to target the American market. Established in 2007, the NXDN Forum currently has 15 members. The protocol for the standard has remained unpublished.

The DCR describes a digital two-way radio standard formulated by Japanese companies, such as ICOM and KENWOOD to target the digital two-way radio market. The final version of the standard is known as ARIB STD-98.

As an open digital two-way radio standard, the narrow digital radio (NDR) standard was formulated by the DRA alliance of digital two-way radio makers. The alliance comprises
24 members, such as China's leading two-way radio manufacturers, renowned colleges and universities, and research institutes. As the alliance's secretariat, director, general technology leader and a leading technical group, Hytera is responsible for drafting, revising, and promoting the standard and submitting the standard for review.

Note:
(1) For more information about dPMR, visit  http://www.dpmr-mou.org/  
(2) For more information about NXDN, visit  http://www.nxdn-forum.com/

Abbreviated for Project 25, P25 was jointly formulated and implemented by American International Public Security Communications Official Association (APCO), National Association of State Technology Directors (NASTD), and Federal Government Users and Telecommunications Industry Association (TIA, a generally accepted standardization organization). As one of the global open digital communications standards listed by International Telecommunication Alliance (ITU), the standard is binding upon radio industry users.

Main standard-setting participants include Motorola and M/A-COM. Currently, major P25 product vendors are Motorola, EFJohnson, Harris, and EADS.

For more information, visit  http://apcointl.org/frequency/project25/information.html  

1. Market Positioning (Applicable Industries)
The P25 standard is suitable for high-end users in the fields of army, public security, transportation, and emergency communications. The U.S. has even earmarked the
700 MHz frequency band for P25 products in the public security area.

 2. Global Distribution
The P25 standard is mostly used in the American market and rarely used in the Middle East, Asia Pacific, and Russia.

 3. Main Features
The P25 standard is evolving in two stages. In the first stage, P25 Phase I employs the frequency division multiple access (FDMA) technology, with 12.5 kHz channel bandwidth, a data rate of 9.6 KB/s, and compatibility with digital/analog modes. In the second stage, P25 Phase II builds on the TDMA double time slots technology, with channel bandwidth equivalent to 6.25 kHz, an uplink data rate of 9.6 KB/s, and a downlink rate of 12 KB/s.

The P25 standard features strong compatibility and a broad supplier base. The P25 open standard supports compatibility and portability between products from competitive manufacturers. 25 digital two-way radios in Phase I provide backward compatibility with analog two-way radios. P25-compliant devices are future-proof as the P25 standard supports the following capabilities: Digital voice and data communication encryption; Enhanced spectrum efficiency over narrower bandwidth. The P25 Standard can divide a 12.5 kHz system into 6.25 kHz or equivalent spectrums; High-quality voice. The P25 standard is based on macro cells. As a single station covers a large area, the number of base stations is small.

Therefore, the standard is suitable for users that require wide coverage and complex dispatching applications.