Frequency Choice

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1 ISM Bands

ISM Bands (or Industrial-, Scientific- or Medical Frequency Bands) are attractive frequency ranges for the deployment of Radar equipment. Choosing a frequency in one of those bands reduces the effort to meet necessary regulations. The ISM frequency bands of interest for Silicon Radar products are situated in the range of 24 GHz, 60 GHz, 122 GHz, and 244 GHz. The exact frequency bands are depicted in Table 1. Indifference to the common belief, some parts of these ISM bands still require licensing. More details can be found in the corresponding standardization bodies and documentations. Also, pay attention to national differences which may apply to broader frequency range allocations. In the end, each operator is held responsible to respect these limits when operating radar devices. This applies as well to the power transmission, which shall not exceed 100 mW Equivalent Isotropic Radiated Power (EIRP) for the four bands indicated.

Table 1: ISM Bands
Frequency Frequency Range Bandwidth Thereof license free(*1) License free bandwidth(*1)
24 GHz 24.00 - 24.25 GHz 0.25 GHz 24.15 - 24.25 GHz 0.10 GHz
61 GHz 61.00 - 61.50 GHz 0.50 GHz 61.00 - 61.50 GHz 0.50 GHz
122 GHz 122.00 - 123.00 GHz(*2) 1.00 GHz 122.25 - 123.00 GHz 0.75 GHz
244 GHz 244.00 - 246.00 GHz 2.00 GHz 244.00 - 246.00 GHz 2.00 GHz

(*1) Please check your exact local regulations.

(*2) FCC proposal to extend ISM starting from 116 GHz up to 123 GHz in the US market.

More relaxed regulations apply for tank level probing radar (TLPR) applications, provided the sensor is kept in a closed environment.

Table 2: TLPR Bands
Frequency Frequency Range Bandwidth
24 GHz 24.05 - 27.00 GHz 2.95 GHz
61 GHz 57.00 - 64.00 GHz 7.00 GHz
80 GHz 75.00 - 85.00 GHz 10.00 GHz

Please note country-specific variations for TLPR applications due to differences in regional regulations.

The European Telecommunications Standards Institute (ETSI) and Federal Communications Commission (FCC) also work on a number of new regulations to open further frequency bands for specific applications and operating conditions. As an example please refer to a technical report which shall foster the introduction of a harmonized spectrum for sensor or radiodetermination applications of Short Range Devices (SRD) using UWB technology within the frequency range 120 GHz to 260 GHz, available under Such initiatives are often available in draft versions and the implementation into regulation still requires approval.

Automotive Radar

As a further example here we refer to the automotive radar frequency domain :

Automotive 24 GHz : The unregulated 24 GHz narrowband (NB) spans 200MHz, from 24.05 GHz to 24.25GHz. The 24GHz Ultra Wide Band (UWB) spans 5GHz, from 21.65GHz to 26.65GHz but will be phased out in 2022 for both, Europe and the USA.

Automotive 77 GHz : The total frequency band spans from 76 GHz to 81 GHz, thereof the automotive Long Range Radar (LRR) band from 76 to 77 GHz and the automotive Short Range Radar (SRR) band from 77 to 81 GHz.

Please note that automotive radar components will require a complete AEC-Q100 certification which may impose a further cost on the components used.


The overview above cannot replace individual information and efforts for the release of sensor solutions on the customer side. No warranty is given, errors and omissions excepted.

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2 Pros-Cons Discussion

If you plan your own sensor application several parameters need to be considered in a Pros and Cons overview. Just to highlight a few radar specific topics, there are the following:

  • the choice of the radar principle CW, FMCW, or pulsed radar
    • CW is essentially useful for detecting movements
    • FMCW also enables the distance measurement for a constant positioning
    • pulsed radar may offer advantages w.r.t. to available power (and reach or dynamic range) of single-pulse signals
  • the choice of the channel count starting from single channel up to massive MIMO configurations
    • single channel transceiver allows an easy, cost-efficient sensor solution for distance and speed measurements
    • multi-channel transceiver is required for resolving angular information and higher object resolution
  • the choice of the frequency range
    • will affect the antenna size
    • the attenuation of the radar beam transmitted
    • the available frequency band

The correct choice of these parameters depends on the specific use case and a generalized answer therefore not available. However, our Sales and Support team is pleased to support you with the right choice for your application.

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3 Export Questions

Export Questions have to be considered regarding wide-band and high power radar sensor solutions but also depend on the country of destination. If you plan to design-in radar MMIC for such sensor solutions export regulations and limitations are preferably taken into consideration at an early stage of development in order to assure the access of all target markets. For further information applying to your specific solution please inquire with our sales team.

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4 Certification after FCC / ETSI

Radar sensor products require, like every product, a certification issued by FCC and CE representatives. During the design-in of Silicon Radar MMICs, we can support you with the identification of the right certification body for your application.

Detailed information on frequency usage in Germany is available from Bundennetzagentur [1]. For Short-Range devices such as our Radar Transceiver you can find operation details under bullet point "Funkanlagen geringer Reichweite (SRD)".

Specifically, when operating radar within the ISM-Band, the subdirectory document "Funkanwendungen mit geringer Reichweite; Non-specific Short Range Devices" applies. Within ISM-Band a CE label is not mandatory but advantageous. However, for an operation outside of the ISM-Band, the document about "UWB-Ultra Wide Band" applies. Here a CE label for the intended product is mandatory.

Specific requests concerning the licence process for products can be send to the Bundesnetzagentur, Referat 424 under 424.Postfach<at>

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5 Frequency Bands

Commonly used notation for microwave frequency bands:

Table: Frequency Bands
Frequency Frequency Range Wave Length (1)
C band 3.95 to 5.80 GHz 79.5 to 51.7 mm
J band 5.85 to 8.20 GHz 51.3 to 36.6 mm
X band 8.20 to 12.4 GHz 36.6 to 24.2 mm
K_u band 12.4 to 18.0 GHz 24.2 to 16.7 mm
K band 18.0 to 26.5 GHz 16.7 to 11.3 mm
K_a band 26.5 to 40.0 GHz 11.3 to 7.5 mm

Table: Interleaved Frequency Bands
Frequency Frequency Range Wave Length (1) Frequency Frequency Range Wave Length (1)
Q band 33.0 to 50.0 GHz 9.1 to 6.0 mm U band 40.0 to 60.0 GHz 7.5 to 5.0 mm
V band 50.0 to 75.0 GHz 6.0 to 4.0 mm E band 60.0 to 90.0 GHz 5.0 to 3.3 mm
W band 75.0 to 110 GHz 4.0 to 2.7 mm F band 90.0 to 140 GHz 3.3 to 2.1 mm
D band 110 to 170 GHz 2.7 to 1.76 mm G band 140 to 220 GHz 2.1 to 1.36 mm
Y band 170 to 260 GHz 1.76 to 1.15 mm J band 220 to 325 GHz 1.36 to 0.92 mm
260 to 400 GHz 1.15 to 0.75 mm 325 to 500 GHz 0.92 to 0.60 mm
400 to 600 GHz 0.75 to 0.50 mm 500 to 750 GHz 0.60 to 0.40 mm
600 to 900 GHz 0.50 to 0.33 mm 750 to 1100 GHz 0.40 to 0.27 mm

(1) Wave Length in free space.

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6 Frequency Regulation

6.1 Preface

The frequency band accessible for radar applications strongly depend on the type of application for emitter, transmitter, and receiver set-ups. A generalized answer or even warranty for the successful license of a radar sensor cannot be given at this place. Therefore we encourage our customers to contact their certification body in an early stage of the design phase!

However, the first introduction on frequency band regulation as it applies to radar sensors shall be given at this place. Integrated Circuits for Short Range Devices (SRD), as manufactured by Silicon Radar, address a frequency range starting from below 10 GHz up to 325 GHz, commonly known as radio frequencies.

Detailed information on radio frequency allocation is given by several standardization bodies which publish tables and overview documents for the region of their responsibility. Here the International Telecommunication Union (ITU) addresses three regions of countries in Europe, America, and Asia which are summarized in the following chart: Local differences between individual countries need to be taken into consideration too - again standardization remains an ongoing challenge. Nevertheless, there is a tendency for harmonization of frequency allocations.

6.2 Sensor Application and Range of Operation Frequency

The scope of the sensor application strongly determines which regulation of operation frequency applies. The frequency regulation distinguishes among others between application purposes such as for amateur, non-specific SRD, radiolocation, level probing radar (LPR), and tank level probing radar (TLPR). For SRD it is often attractive to deploy frequencies of the Industrial, Scientific, and Medical (ISM) frequency bands which are centered around 24.15 GHz, 61.25 GHz, 122.65 GHz, and 245.00 GHz. A complete overview of bandwidth details on page In frequency tables of national and international regulators, details about ISM frequency are often summarized in the annex under amendments No. 1.138 and 1.150.

For applications such as tank level probing radar (TLPR) more relaxed frequency restrictions apply. But, as soon as the sensor application also covers open reservoirs and basins these limits narrow again (LPR). In such an application landscape the design of adaptive sensor solutions proves to be advantageous. Finally, it should be mentioned, that well-shielded test labs and devices for R&D investigations may provide further frequency options. However, a prior, careful and comprehensive review for every application shall be mandatory for sensor developments.

6.3 Summary of World Regions Frequency Allocation

The frequency map is subdivided into three world regions which are displayed e.g. in

An overview of Frequency Allocations in all three world regions for a frequency range from 10 to 275 GHz can be found in

A graphical summary on frequency assignment for the three world regions has been summarized as a white paper and is available as a download here [registration for download required]:

6.4 International Country List

Some webpages offer an overview to frequency allocation tables of specific countries, worldwide

Source #1

Source #2

Source #3

Source #4

6.5 European Area

For the European area, the European Conference of Postal and Telecommunications Administrations (CEPT) publishes an overview on regulations concerning the radio frequencies here

More selective an information system for the ITU-Region 1 provides details for the country and frequency range of interest in a web-based inquiry system under

If national information are preferred, the overview on page will guide to the documentory of interest.

Among EU countries also watch out for non-EU countries! Therefore please refer to the following pages:

Norway provides information under

Switzerland offers information on page

United Kingdom now outside EU legislatoin also keeps information up to date under and

Island as member of EU translates EU-wide regulation into national law under

Turkey - Additional information on frequency deployment for Turkey can be found on page under Milli Frekans Planı, stored in URL:

Russia provides this information as a table at following places - and and as frequency map here -

6.6 North America

The USA - The summary for the American market is published, among others, in the frequency table of US authority FCC in the ONLINE TABLE OF FREQUENCY ALLOCATIONS open to the public under An overview on one page is given in a spectrum wall chart under

Canada supports its own frequency table under

6.7 Asia-Pacific & Oceania

A web platform to access information on selected countries of Asia and beyond (ITU-Region 3) is available here - Furthermore, a table with the status and the outlook of frequency allocations for short-range devices is summarized in a table under

Some countries shall be highlighted here separately:

People's Republic of China provides an overview subdivided into sections for Mainland China, Hongkong, Macao, and ITU Region 3 as a reference here: and details about certifications are explained under .

In parallel for the Taiwanese area, an English edition is distributed here -

India -

Indonesia -

Bangladesh -

Japan - with a summary of the radar frequency allocations above 10 GHz as wall chart in

Singapore has published its frequency regulation in tables and as chart under

Mongolia publishs its frequency allocation plan in tables -

6.8 Middle and South America

Information on Frequency Band Allocations are available for individual countries as follows:

Argentina -

Brazil -

Chile -

Mexico - download in

Peru -

Venezuela -

6.9 Middle East

Frequency Tables are available for

United Arabic Emirates (UAE) -

Saudi Arabia -

Pakistan -

6.10 Africa

A group of 15 southern African countries [remark #1] have published the SADC Frequency Allocation Plan (SADC FAP) for frequencies between 8.3 kHz and 100 GHz in Maseru, Lesotho in May 2013 -

Furthermore, countries publish their regulation plan for frequency allocation separately hereafter

Morocco - and a revised version

Tunesie -

Libya -

Egypt -

Nigeria - and

Kenya -

Uganda -

South Africa -

Remark #1:

Participating countries are Angola, Botswana, Congo, Lesotho, Madagascar, Malawi, Mauritius, Mozambique, Namibia, Seychelles, South Africa, Swaziland, Tanzania, Zambia, and Zimbabwe.

6.11 Australia & New Zealand

Frequency Tables are available for

Australia -

New Zealand - and in Another overview (2016) is available here

6.12 Earth-Satellite, Orbit and Deep Space

Due to the low attenuation and dramatic distances, a deployment of RF devices in space applications requires special care in order to keep the accumulated radiation load at a minimum.

Earth-Satellite: Some information on frequencies used between Satellites and Earth Surface is described in, for the well-known broadcaster frequencies cf. page 10.

Orbit: Satellite communication is a topic of ongoing discussion, currently fostered by the expansion of non-geostationary satellite systems in MEGA constellations. Information and discussion of satellite communication frequencies are coordinated by ITU's Space Services Department (SSD), cf. The activities are described in a number of presentations of the ITU such as in the slide show under Already applied frequencies can found using the request pages such as

Deep Space: Radio Astronomy applications require a selected table of frequencies, most often defined by resonance frequencies of molecules. Therefore artificial transmitter shall omit such frequencies and the vicinity of such characteristic frequencies as listed e.g. under

6.13 Outlook: ITU Conference WRC-19 & Beyond

New information and final releases are also expected from the conference of the ITU conference on radio regulations World Radio communication Conference 2019 (WRC-19), Sharm el-Sheikh, Egypt, 28 October to 22 November 2019. Details of the conference can be found in

Several preparatory considerations were summarized beforehand, e.g. in

Some results are covered in and in a provisional final acts frequency listing to be found under

Further activities and ongoing work are bundled in and will be published from study groups. An overview of study groups can be found on Activities include topics like "frequency regulation such as for the consideration of sharing and adjacent-band compatibility between passive and active services above 71 GHz".

Furthermore, the European Telecommunications Standards Institute (ETSI) and Federal Communications Commission (FCC) also work on a number of new regulations which shall foster the introduction of a harmonized spectrum for sensor or radiodetermination applications of Short Range Devices (SRD) using UWB technology within the frequency range 120 GHz to 260 GHz, available under

6.14 Disclaimer

The information above is given for orientation, only. It cannot replace individual information and efforts for the release of sensor solutions on the customer side. No warranty is given, errors and omissions excepted.

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