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Jie Kao Ao (JQL) Electronics manufactures RF and microwave circulators, isolators, iso-adapters, ceramic filters, cavity filters, hybrid combiners, power splitters, couplers and low PIM terminations with excellent quality at a very reasonable price. Company brochure JQL

RF and Microwave Circulators and Isolators

Ferrite circulators are passive three-port devices in which an RF or microwave signal is transmitted from one port to the next port, but not to the third port. They are mainly used to protect amplifiers from reflected signas if there is a defect in the cable or antenna after the amplifier. Another usage is the separation of transmitted and received signas in systems which operate in the same frequency band for transmission and reception, e.g. RFID. The ports are matched inside the housing or on the microstip board to 50 Ohm. RF isolators have one port terminated with a power resistor.

JQL offers a complete spectrum of coaxial, drop-in, surface mount, microstrip, and waveguide ferrite circulators and isolators, from 100MHz to 120GHz, for all communications and radar bands: VHF, UHF, TETRA, GSM, ISM (868MHz, 915MHz, 2,4GHz, 5GHz, 24GHz), UMTS, LTE, 5G, L-band, S-band, C-band, X-band, Ku-band, K-band, Ka-band, E-band, W-band.

JQL low IMD coaxial circulator Coaxial Circulators and Isolators

  • 100MHz to 28GHz
  • up to 500W average power
  • single circulator and high isolation dual coaxial circulator and isolator designs
  • connector options: N, SMA, K-connectors
  • short lead times, aso for custom designs

Drop-In Circulators and Isolators

  • 100MHz to 40GHz
  • up to 500W average power, up to 6000 Watt peak power
  • single circulator and high isolation dual coaxial circulator and isolator designs

Surface Mount Circulators and IsolatorsJQL surface mount circulator

JQL microstrip RF isolatorMicrostrip Circulators and Isolators

  • 5GHz to 36GHz
  • up to 20W average power
  • compact designs, small form factor (6.35mm at X-band)
  • high isolation of 18dB to 23dB
  • ideal for Ka-band phased array radar and radio links

Waveguide Circulators and IsolatorsJQL waveguide circulator

  • 4.4GHz to 100GHz
  • up to 350W average power
  • waveguide sizes: WR187, WR112, WR90, WR75, WR62, WR51, WR42, WR34, WR28, WR22, WR18, WR14, WR10
  • high isolation of up to 28dB
  • low insertion loss of 0.3dB at 30GHz

Coaxial Cavity Filters

JQL cavity filter bandpass

These coaxial filters use cavity resonances to achieve high Q and thus low insertion loss, steep skirts and high isolation. JQL offers various categories of cavity filters. All standard designs can be modified easily and quickly to meet customer specific requirements.

Bandpass Cavity Filters

200MHz to 15GHz, SMA- or N-connectors, as drop-in or with horizontal pins.
New: cavity filters for 915MHz (datasheet)

Low Pass Cavity Filters

Band edge 450MHz or 500MHz

Coaxial Cavity Duplexers and Diplexers

JQL cavity filter duplexerFor center frequencies from 100MHz to 40GHz

Coaxial Cavity Triplexers

With three internal bandpass filters, for teh cellular frequency bands of GSM, UMTS and LTE

Coaxial Cavity Quadplexers

E.g. Quadplexer for EGSM900, UMTS2100, LTE800 and LTE2600

Cavity Multiplexers for 5 or 6 Cellular Frequency Bands

Cavity Filters for PIM Testing

Special high performance filters for test equipment which measures Passive InterModulation (PIM) distortion.
At 2x20W the PIM value is <-171dBc.

Coaxial Low PIM Terminations

Broadband (DC to 3GHz) terminations with low intermodulation distortions for power levels from 5W to 100W with SMA, N, 7/16 or 4.3-10 connectors. Datasheet J-4.3-10-50JR-50W JQL ceramic filter bandpass

Ceramic Filters

Ceramic Bandpassfilters

New: ceramic filter for C-band (datasheet)

Ceramic Duplexers and Diplexers

E.g. Diplexer for GSM900 and UMTS

Ceramic Triplexers JQL low PIM reactive power splitter

Ceramic Quadplexers

Coaxial Low-PIM Power Dividers

Reactive 500W RF power divider with low Passive InterModulation distortions (low PIM):
<-160dBc at 2x20W (2x43dBm).
JQL low PIM bias tee

Low-PIM DC-Blocks

Low-PIM Bias Tees

Bias Tees for cellular frequency bands  (690MHz to 2,7GHz) with low insertion loss (0.15dB) and low PIM (<-160dBc at 2x20W).

Coaxial Low-PIM Directional CouplersJQL coaxial low pim directional coupler

  • Directional couplers with low intermodulation distortions for DAS (Distributed Antenna Systems)
  • For PMR and cellular bands of TETRA, GSM, UMTS (3G), LTE (4G) and 5G
  • Frequency range 380MHz to 3.6GHz
  • Insertion loss less than 0.3dB
  • PIM < -140dBc at 2x20W
  • Coupling factors: 6dB, 10dB, 15dB, 20dB, 30dB, 40dB

Coaxial Low-PIM Terminations

JQL produces broadband (DC to 3GHz) coaxial terminations with low passive intermodulation distortions for RF power levels from 5W to 100W, with SMA, N, 7/16 or 4.3-10 connectors. Datasheet J-4.3-10-50JR-50W

Waveguide-Coax-AdaptersJQL coax waveguide adapter

Adapters from waveguide to SMA-, N- or K-connector

Power Dividers, Directional Couplers, Iso-Adapters

Overview Power Dividers
Catalog Standard Directional Couplers (800MHz bis 2.5GHz)
Catalog Iso-Adapters for C-Band, X-Band and Ku-Band