70 centimeter tape

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The frequency range from 400 MHz to 470  MHz is called the 70-centimeter band . The name is derived from the approximate wavelength of this frequency range.

This frequency range is used by commercial radio , BOS radio and the amateur radio service (primary use 430–440 MHz). Handheld radios are often used in this frequency range. In order to achieve a long range with low power with these devices, relay stations are used.

Propagation conditions

Radio waves of these (and higher) frequencies spread quasi-optically. This means that even a few obstacles between the transmitter and receiver can severely impair the connection. This is why the maximum ranges are rarely achievable in everyday life.

70 centimeter amateur band

The European 70 cm amateur band uses the frequency range from 430 to 440 MHz. In other countries the frequency range from 420 to 450 MHz is assigned to amateur radio. It is the lowest frequency band in which amateur radio television is allowed. A large area of ​​the 70 cm band is approved for operation via amateur radio satellites ; this area is kept free for 70 cm from the band plan .

Band plan

Frequency range use
430,000-432,000 MHz subregional band planning
432.000-432.100 MHz CW
432,100-432,400 MHz CW and SSB
432.400-432.490 MHz CW beacons (please no broadcasting)
432,500-432,600 MHz Input of linear transponder
432,600-432,800 MHz Output linear transponder
432,800-435,000 MHz all operating modes
435,000-438,000 MHz Amateur radio satellites
438,000-440,000 MHz subregional band planning
  • Relay stations
  • Packet radio
  • 439.9875 MHz paging ( POCSAG )

70 centimeter BOS tape

This band is often used as a directional radio link for single-frequency radio systems or DAU .

450 MHz band

From 1985 to 2000, the analog cellphone network C-Netz was operated in Germany between 451 and 466 MHz . Thereafter, this band was allocated two frequency blocks to 450Connect GmbH and one frequency block to Telekom Deutschland GmbH , each with a channel bandwidth of 1.25 MHz. The awards are limited to December 31, 2020. The Federal Network Agency initiated a frequency plan change for this frequency range on July 12, 2017. A term of 20 years is planned for the reallocation.

With a view to the needs of the operators of critical infrastructures for secure communication and the fact that the operators of critical infrastructures have not yet been given an exclusive dedication in the frequency plan, the Federal Network Agency intended to make the frequencies available nationwide for these users. In the context of technology neutrality, LTE operation should be provided. In the meantime, the BOS and the Federal Armed Forces are also demanding the use of this frequency band for their own purposes.

Although it is only a relatively narrow-band spectrum of 2 times 4.74 MHz (451.00 - 455.74 MHz and 461.00 - 465.74 MHz), the frequencies that were released were due to their good propagation properties (large range, good penetration into the basement) very popular from the start. In an initial demand survey by the Federal Network Agency in 2017/2018, around 50 notifications and statements were submitted. In particular, energy and water suppliers as well as telecommunications companies, but also associations and manufacturers, registered requirements. In addition, the authorities and organizations with security tasks (BOS) as well as the Bundeswehr demanded exclusive use of the frequencies.

The operators of critical infrastructure in the energy justify the need for a radio network in the 450 MHz band, among others, to the control and observability by network operators in the Black case , the secure mobile voice communication in disorders and in crisis situations, the connection and grid integration of distributed generation, storage and Loads and the improvement of the availability of network-serving telecommunications services.

The Federal Agency for Digital Radio for Authorities and Organizations with Security Tasks (BDBOS) argues in favor of assigning the frequencies to the BOS by stating that emergency and rescue forces need modern, mobile means of communication to cope with their daily operations, whereby broadband applications are also becoming increasingly important. Therefore, a secure and highly available broadband network for the police, fire brigade, rescue services and the German armed forces is essential, for which an allocation of the 450 MHz frequencies is an indispensable requirement.

The Federal Network Agency has asked the Federal Ministry of Transport and Digital Infrastructure (BMVI) to take the decision on the allocation of the frequency at the level of the frequency plan. The BMVI then wanted, in agreement with the Federal Ministry for Economic Affairs and Energy (BMWi) and the Federal Ministry of the Interior, for Building and Home Affairs (BMI), to commission an expert opinion that was to serve as the basis for the award decision. In August 2019, the BMWi finally presented a report prepared under the leadership of the Scientific Institute for Infrastructure and Communication Services (WIK). The experts come to the conclusion that a dedicated mobile network for critical infrastructures in the 450 MHz frequency range could meet the special requirements at the lowest possible cost and that the upcoming reassignment of usage rights represents a great opportunity for the energy transition. In September 2019, the Advisory Board of the Federal Network Agency endorsed the judgment of the report commissioned by the BMWi and advocated the allocation of frequencies to the critical infrastructures of the energy industry.

BDBOS President Gegenfurtner turned to the energy industry in an open letter in mid-September 2019 and again pleaded for an allocation to the BOS. In October 2019, the energy and water industry responded with its own open letter in which it advocates the allocation of 450 MHz frequencies to the critical infrastructures of the energy and water industry. In January 2020, the Federal Minister of the Interior again spoke out clearly in favor of the BOS. In view of the continuing differences between the interests of the BMWi on the one hand and the BMI on the other, the responsible Federal Network Agency passed the award decision to politicians.

In view of the imminent expiry of the frequency assignments at the end of 2020, the Federal Network Agency finally published key points and a renewed assessment of the future use of the frequencies, subject to a decision by the federal government. The total of 132 comments received from associations, companies and other stakeholders were published on the Federal Network Agency's website in mid-April 2020.

Other users

The range from 433.05 to 434.79 MHz is called the ISM band (secondary use), e.g. B. for wireless thermometers, wireless switches ( car keys with Keyless Go , wireless sockets, LPD, etc.). These SRDs have a maximum power of 10 mW and 69 channels and are free of charge. The range is 0.3 km (in the city) to max. 2.5 km (in open space). This frequency range is also used by the amateur radio service. Interferences from the amateur radio service have to be accepted.

The range from 446.00625 to 446.19375 MHz is provided with 16 channels and a maximum power of 500  mW ( ERP ) for PMR radio . Due to the higher performance, the ranges are slightly better than LPD devices at 0.5 to 5 km in open space. Newer baby monitors also work in this area .

literature

Web links

Individual evidence

  1. Radio amateur: FM radio at 2 m and 70 cm - channel list (PDF; 848 kB)
  2. a b c d Determination of frequency requirements and key points for future use of frequencies in the 450 MHz band on the website of the Federal Network Agency, accessed on April 7, 2020
  3. Annual table of contents 2017 of the Official Gazette of the Federal Network Agency , Official Gazette 24/2017 of December 20, 2017, Ordinance No. 700/2017
  4. 450 MHz frequency range for the critical infrastructure energy supply , position paper of the VDE FNN, accessed on April 7, 2020
  5. a b Federal Minister of the Interior Seehofer: Blue light organizations must receive 450 MHz frequencies! , Article on the BDBOS website, January 31, 2020
  6. a b 450 MHz as an opportunity for the energy transition: BMWi publishes report on telecommunications infrastructure for the digitization of the energy transition , BMWi press release including a link to the report, August 20, 2019
  7. Advisory board endorses 450 MHz frequency use by the energy industry , press release by the Federal Network Agency, 23 September 2019
  8. Open letter to the energy industry and their supporters in the 450 MHz frequency allocation , on the BDBOS website, September 13, 2019
  9. Open letter from the energy and water industry on the urgent need to allocate the 450 MHz frequencies , joint press release from BDEW and VKU, October 23, 2019