Frequently Asked Questions

You can submit your inquiry simply via our contact form or by email to info@bq-microwave.de. If possible, specify the desired manufacturer, model, and quantity. If you don't find exactly what you need, just tell us your desired product with your technical requirements — we'll validate the specifications and advise you on the selection. We typically respond within one business day with a concrete quote.

Yes. The minimum order value is €250 net. For smaller orders, we charge a small order surcharge of €25. This covers the administrative and logistics effort for very small deliveries.

We supply research institutes, universities, defense and satcom manufacturers, 5G/6G development labs, and OEM manufacturers in the test & measurement and EMC sectors. Private individuals are not our target customer base.

Yes. For research and development projects, we offer samples or evaluation boards depending on the manufacturer and component. Contact us with your application case and we'll check availability with the manufacturer.

There is no standard flat delivery time. Stock items in the USA and China can often be delivered within 1–2 weeks. Non-stock coaxial components — modules, cables, switches, amplifiers — typically require 4–6 weeks. Non-stock modules and systems in the millimeter-wave range require approximately 8–12 weeks. We provide the exact delivery time for your requested products with binding confirmation in the quote.

Yes. Our prices include 3.7% customs duty. You receive the goods with no further customs clearance required — DDP, delivered free within the EU.

Yes. We deliver to all EU countries as well as to Switzerland, Norway, and the United Kingdom. Our sales territory covers all of Europe including the UK.

We use antistatic, individually protected packaging for RF and microwave components according to each manufacturer's guidelines. Shipping is via air freight (international) or UPS, DHL Express, or DPD (Europe) — always with full tracking and insurance.

Standard payment is by bank transfer against invoice. For first orders or certain situations, we reserve the right to require prepayment. We do not offer credit cards, PayPal, or direct debit in B2B business.

Our standard payment term is 14 days net from invoice date. Different payment terms can be individually agreed upon.

We carry over 17 specialized manufacturers in the RF, microwave, and millimeter-wave sectors, including AT Microwave, Vaunix, TMYTEK, Magvention, Elmika, SHX, Rofea, and many more. A complete overview can be found on our manufacturers page.

Our portfolio ranges from DC to over 1,700 GHz (WR-0.65). In the waveguide range, we cover all standard bands from WR-2300 to WR-0.65. In the coaxial range, we supply up to 145 GHz.

We supply waveguide components in all common WR sizes from WR-2300 to WR-0.65 as well as in the broadband WRD double-ridge standards from WRD-180 to WRD-180C24. A complete overview of WR and WRD standards with frequency ranges can be found in the following question.

The WR designation (Waveguide Rectangular) follows the EIA standard and describes the inner dimensions of a rectangular waveguide. The number corresponds to the broad inside dimension in hundredths of an inch — WR-10 means 0.10 inches or 2.54 mm. With smaller WR numbers, usable frequencies increase, because smaller waveguides can carry higher frequencies. The following table shows all common WR standards from 320 MHz to 1.7 THz with their frequency ranges and typical applications:

WRD stands for Waveguide Rectangular Double-Ridged — a rectangular waveguide with two internal ridges that enables a significantly larger usable bandwidth than a standard WR (typically 2:1 to 3.6:1). The number in the designation indicates the lower frequency limit in 100 MHz increments — WRD-350 starts at 3.5 GHz. WRD waveguides are used where broadband transmission in a single waveguide is required, such as in EMC antennas, test setups, broadband amplifiers, and measurement systems.

We supply components with all common RF and precision connectors: SMA (up to 18 GHz), 3.5 mm (up to 26 GHz), 2.92 mm / K (up to 40 GHz), 2.4 mm (up to 50 GHz), 1.85 mm / V (up to 67 GHz), 1.0 mm (up to 110 GHz), as well as waveguide flanges in all standard sizes. Which interfaces are available for your specific model can be found in the respective datasheet — feel free to contact us.

Yes, across the entire 5G/6G spectrum. For 5G FR1 (Sub-6 GHz), Wi-Fi, and the lower FR2 segment, we supply USB-programmable test components from Vaunix — attenuators, phase shifters, and switches as well as signal generators with a frequency range from 0.5 MHz to 40 GHz, ideal for channel emulation, phased array testing, and local oscillator applications. For 5G FR2 (mmWave), TMYTEK offers complete FR2 coverage from 24 to 44 GHz with the BBox beamformer and UD-Box frequency converter family, including all relevant n257–n261 bands. For 6G research in D-band (110–170 GHz, WR-6.5) and beyond, we carry mmWave modules from AT Microwave, Magvention, and Elmika, as well as matching waveguide components into the sub-THz range. This way we cover 5G/6G from Sub-6 GHz testing through FR2 beamforming to submillimeter research in a single portfolio.

Yes. Many of our manufacturers produce custom components — whether for frequency range, power, connectorization, or mechanical specifications. Contact us directly with your requirements, and we'll check feasibility and obtain a quote from the manufacturer.

Datasheets are typically provided along with the quote. They can always be requested by email or are available for download on the product pages of the respective manufacturers. CAD models (STEP/IGES) are provided upon request in coordination with the manufacturer.

A coaxial line carries the signal via two concentric conductors (inner conductor and outer conductor) — it is flexible, compact, and usable for frequencies up to approximately 110 GHz. A waveguide, on the other hand, is a hollow, typically rectangular metal channel in which electromagnetic waves propagate. Waveguides have significantly lower losses, can handle higher power levels, and are the standard from the millimeter-wave range (typically above 26 GHz). Coaxial is used in cabling and lower frequencies, waveguide in mmWave, SatCom, and THz applications.

The choice of connector type is primarily determined by the maximum operating frequency. Proven standards are: SMA up to 18 GHz (standard for microwave applications), 2.92 mm / K-connector up to 40 GHz, 2.4 mm up to 50 GHz, 1.85 mm / V-connector up to 67 GHz, 1.0 mm up to 110 GHz. At high frequencies, mechanical tolerances decrease drastically — even dirt or slight damage to the connector can cause measurable losses or reflections. In the mmWave range above approximately 40 GHz, waveguide connections are often preferred over coaxial connectors in many applications.

VSWR (Voltage Standing Wave Ratio) and Return Loss are two different representations of the same quantity — they describe how well an RF component is impedance-matched and how much signal is reflected at its input. An ideal VSWR value would be 1.0:1 (no reflection). In practice, values below 1.5:1 are very good, values up to 2.0:1 are acceptable for most applications. Expressed in dB: Return Loss greater than 14 dB corresponds to a VSWR below 1.5:1; more is better. Poor matching leads to signal losses and can cause unwanted effects in sensitive circuits.

Insertion loss indicates how much signal power is lost when passing through a passive RF component. It is specified in decibels (dB) — the lower the value, the better. For a bandpass filter, the insertion loss in the passband could be, for example, 0.5 to 2 dB. For long waveguide sections at high frequencies, it can reach several dB per meter. Insertion loss consists of ohmic losses in the conductors, dielectric losses, and reflection losses due to mismatch.

RF and mmWave components are found wherever electromagnetic waves are used for communication, detection, or measurement. Key application areas include: satellite communications (SatCom), mobile communications (4G/5G/6G), radar technology (civil and military), automotive radar (77 GHz, driver assistance), scientific research (radio astronomy, plasma research), medical technology, security scanners, and test and measurement. In all these areas, typical components — amplifiers, filters, mixers, couplers, isolators, antennas — are deployed, each tailored to the required frequency range and power class.

Satellite communications typically operate in the C (4–8 GHz), X (8–12 GHz), Ku (12–18 GHz), K (18–27 GHz), and Ka (27–40 GHz) bands. Modern systems are increasingly utilizing the Q/V band (33–75 GHz) and W band as well. Ground stations require antennas with polarizers, low-noise amplifiers (LNA, LNB), filters, mixers, and frequency converters — very often in waveguide construction due to low losses. In the transmit chain, high-power amplifiers (HPA, TWTA), isolators, circulators, and bandpass filters are deployed.

5G uses two frequency ranges: FR1 (Sub-6 GHz) and FR2 (mmWave, 24–52 GHz). In the FR2 range, phased array antennas with many individual radiating elements and phase shifters are used to electronically steer the beam (beamforming). This requires mixers, filters, amplifiers, and frequency converters in the respective band. 6G is expected to utilize frequencies above 100 GHz into the sub-terahertz range (D-band, 110–170 GHz, and higher). This significantly raises component requirements — smaller wavelengths, tighter tolerances, new materials and manufacturing processes are needed. bq-microwave already carries components well above 100 GHz in our portfolio today.

Modern driver assistance systems use radar sensors at 76–81 GHz (often referred to simply as 77 GHz radar). This band provides globally harmonized bandwidth that enables high resolution and range. An automotive radar sensor requires a signal generator (VCO or PLL), amplifiers, mixers for transmit and receive paths, bandpass filters, and an antenna — all integrated in the tightest space. Typical applications are adaptive cruise control, emergency braking assist, lane change warning, and blind spot detection. With the transition to more highly integrated MMIC solutions, many individual components are now combined on a single chip, but discrete components remain important for test, measurement, and specialty modules.

Yes. We see ourselves not as a pure reseller, but as a technical partner and will advise you on component selection, waveguide sizing, frequency planning, and interface choice within our capabilities. For deeper technical questions, software topics, or application-specific specialty issues, we directly involve the respective manufacturers so you get the best possible answer.

The respective manufacturer's warranty conditions apply, typically 12 months from delivery. Upon request, extended warranty coverage is usually available for an additional fee and by individual agreement with the respective manufacturer — feel free to bring this up during the quote process. In case of a claim, we handle the entire process for you: you send us the goods, we coordinate with the manufacturer, and deliver replacement or repair.

Microwave components are passive or active devices designed for the frequency range from approximately 1 GHz to 30 GHz. They are used to guide, distribute, filter, amplify, or modulate high-frequency signals in a controlled manner. Typical examples include amplifiers, filters, mixers, couplers, isolators, circulators, and phase shifters. Microwave components are found in radar, satellite, mobile communications, and test and measurement applications.

Waveguide components are RF devices where the signal is not transmitted through an inner-outer conductor arrangement like in coaxial cable, but rather through a hollow, metal-bounded tube — typically with rectangular or circular cross-section. Waveguides have a lower cutoff frequency below which wave propagation is not possible. They offer extremely low losses and high power handling capability and are standard in the frequency range from approximately 1 GHz well into the sub-terahertz range.

Millimeter-wave components (mmWave components) are RF devices for the frequency range from 30 GHz to 300 GHz. The wavelength in this range is between 1 mm and 10 mm — hence the name. As frequency increases, components become smaller and mechanically more precise, since tolerances in the micrometer range already affect performance. mmWave components are deployed in 5G/6G, automotive radar (77 GHz), SatCom, defense, and high-precision test and measurement applications.

The term waveguide refers to the construction type — a hollow, metal-bounded transmission structure. The term mmWave refers to the frequency range (30–300 GHz). Both terms overlap but are not synonymous. An mmWave component can be implemented in waveguide form (e.g., WR-15 for V-band) or in coaxial form (e.g., with 1.85 mm connectors). Conversely, there are waveguide components below the mmWave range as well, such as in X-band or Ku-band. In practice, however, waveguide becomes the dominant construction type above approximately 40 GHz, as coaxial connections quickly become lossy at these frequencies.

At high frequencies, due to the skin effect, current flows only in an extremely thin surface layer of the conductor — at 100 GHz, for example, the penetration depth in copper is only about 0.2 µm. Losses are therefore almost entirely determined by the properties of this thin surface. Gold is used as a plating material because it is corrosion-resistant and does not form insulating oxide layers even after years, which would significantly increase losses at mmWave frequencies. While silver has higher conductivity, it tarnishes and is therefore impractical. Gold also offers good solderability and is mechanically wear-resistant during mating cycles.

The radio frequency spectrum is typically divided into the following bands: HF (3–30 MHz), VHF (30–300 MHz), UHF (300 MHz–3 GHz), SHF / Microwave (3–30 GHz), EHF / Millimeter Wave (30–300 GHz), and Sub-Terahertz / Terahertz (above 300 GHz). In practice, IEEE band designations such as L, S, C, X, Ku, K, Ka, V, W, and D are also widely used, especially in satellite and radar technology. bq-microwave supplies components from the lower GHz range well into the mmWave and sub-terahertz range (up to 1700 GHz).

Standard materials include brass and aluminum. Brass offers a good combination of machinability, corrosion resistance, and acceptable conductivity and is the most common choice. Aluminum is lighter and is primarily used where weight matters (e.g., in aerospace applications). For particularly low-loss applications or high frequencies, oxygen-free high conductivity copper (OFHC) or stainless steel are also used. The inner walls are typically plated with gold, silver, or nickel to minimize surface losses and prevent corrosion.

At high frequencies, the skin effect causes current to flow in an extremely thin surface layer. If the surface is rough, the current must follow this roughness, which effectively lengthens the path and increases losses. At 100 GHz, the penetration depth is only about 0.2 µm — surface roughness of the same order of magnitude therefore leads to measurably higher losses. High-quality mmWave components are manufactured with very smooth inner walls (Ra below 0.4 µm) and are carefully polished or electropolished.

The terms are used differently depending on context, but together they cover the entire spectrum of electromagnetic waves used in communications, radar, and sensor technology. HF (Hochfrequenz, German) and RF (Radio Frequency, English) essentially mean the same thing and encompass all frequencies above the audio range (typically from a few MHz). Microwaves are a subset, typically from 1 GHz to 30 GHz. Millimeter waves (mmWave) refer to the frequency range from 30 GHz to 300 GHz, where the wavelength is in the millimeter range.

bq-microwave was founded in 2011 and has since operated as a specialized European distributor for RF, microwave, and millimeter-wave components. We now represent over 17 manufacturers throughout Europe.

Our headquarters is in 71549 Auenwald, Germany (Hohe Str. 23). From here we serve customers throughout Europe.

Primary communication languages are German, English, and Dutch. Our website is available in 12 European languages — we can respond to written inquiries in any of these languages.