SJ FOTI CONSULTING

INTERNATIONAL CONSULTING IN RF, MICROWAVES & ANTENNAS

Sample Projects

The gallery below provides a photograph, caption and a brief description for each of a number of sample projects.

Please click on a thumbnail image to enlarge and view the description.

Electronically Spinning TACAN Antenna (Radome removed)

SJ Foti led the design team as Technical Executive, Antenna Systems, at ERA Technology in developing this product for Cardion Electronics, USA. This antenna operates over the full TACAN band of 962 - 1213 MHz and achieved a worst case bearing accuracy of 0.5 degrees. A novel 'See-Saw' phase shifter was developed for this product as well as a wide band Butler Matrix (both also shown in this gallary). These component developments yielded a highly efficient array feed network.

High Power Phased Array using Ferrite Phase Shifters with Printed Linear-to-Circular Polariser

SJ Foti developed this antenna system for an ECCM application as a Senior Antenna Engineer at American Electronic Labs, Lansdale, Pa, USA. An array of H-plane sectorial horn antenna elements excited by a power divider/combiner through ferrite pahse shifters provided a +/- 60 degree scan angle range.

High Power Electronically Rotating Linearly Polarised Conical Horn Antenna

SJ Foti developed this antenna as a Senior Antenna Engineer at American Electronic Labs, Lansdale, Pa., USA for an ECCM system to determine the jamming vulnerability of a phased array radar antenna system. Back-to-back waveguide magic-Ts with dual-latching ferrite phase shifters maintained equal phase excitations on the two orthogonal conical horn probes and variable apmlitude ratios. This yeilded electronically controlled linear polarisation angle.

Octave Band, Wide Scan Angle Phased Array Antenna using a WAIM Sheet

SJ Foti led the team in developing the advanced antenna system as Technical Executive, Antenna Systems at ERA Technology, Leatherhead, Surery, UK The array achieved +/- 60 degree scan angle coverage over a full octave bandwidth by incorporating a WAIM (wide angle impedance matching) sheet. This minimised the variation of active reflection coefficients.

High Power, Octave Band, Bi-Conical Dipole with Integrated Printed Vertical-to-Slant 45deg Polariser & Double-Ridged Waveguide-to-Coax Transition

Developed by SJ Foti as technical Executive, Antenna Systems at ERA Technology, Leatherhead, Surrey, UK for an airborne ECM application. A unique double-ridged waveguide-to-coax transition was integrated into a bi-conical dipole to provide low VSWR over an octave band,

Discone Dipole with Shorting Pin to achieve a Cardoid Azimuth Radiation Pattern with an integrated Vertical-to-Circular Polariser

SF Foti developed this antenna as Technical Executive, Antenna Systems at ERA Technology, Leatherhead, Surrey, UK for an ECM application.

48-Way Waveguide Power Divider for Ultra-Low Sidelobe Phased Array Radar

SJ Foti conceived the design & led design team as Technical Executive, Antenna Systems, at ERA Technology, Leatherhead, Surrey, UK in developing this product for a Swedish company. The waveguide network consisting of a multiplicity of Branch-Line couplers achieved a worst cast RMS amplitude error of 0.1 dB. The bandwidth normally would have required 8-branch couplers, but a clever interconnection arrangement allowed the required performance to be achieved with 4-branch couplers.

60-Way, Extremely Low-Loss Radial Waveguide Power Divider/Combiner Assembly

SJ Foti developed this state-of-the-art structure, as Principal Engineer at Flam & Russell, Horsham, Pa, USA for combining solid state power amplifiers with a 'graceful degradation' feature in a radar system. This structure achieved a worst case loss of only 0.3 dB and a maximum VSWR of less than 1.5:1. The amplitude balance was +/- 0.3 dB and the phase balance was +/- 4 degrees.

SJ Foti developed this state-of-the-art structure, as Principal Engineer at Flam & Russell, Horsham, Pa, USA for combining solid state power amplifiers with a 'graceful degradation' feature in a radar system. This structure achieved a worst case loss of only 0.3 dB and a maximum VSWR of less than 1.5:1. The amplitude balance was +/- 0.3 dB and the phase balance was +/- 4 degrees.

Developed by SJ Foti at Flam & Russell, LNR Communications & ERA Technology.

Low profile printed circuit BTS antenna.

SJ Foti led the design team at Inotek, Sittingbourne, Kent, UK when he was the founding Director. This antenna technology developed at Inotek was used in competitive field trials for Orange, UK when it out-performed antennas from international competitors and was selected for the Orange network as well as the T-Mobile (then One-2-One) and the 3 network.

Near-Field measurements of dual-polarised BTS antenna

This sector antenna was selected by Orange,UK for its network in competitive field trials.

Dual-Polarised Tri-Sector antenna in a tube developed at Inotek.

The low profile printed circuit antenna technology allowed Inotek to realise a tri-sector antenna in an extremely small diameter tube. Network operators selected this antenna model for deployment in urban areas because of it's low visual impact.

Tri-Sector BTS antenna in a flagpole configuration.

This low visual impact tri-sector antenna (top 1.7m of the flagpole) was developed for T-Mobile (formally One-2-One).

Dual-Polarised dual-band BTS sector antenna

Inotek's low profile antenna technology facilitated high isolation between two BTS antennas in a common radome.

Diagonal Horn Antennas for Optimum Anechoic Chamber Illumination

Developed by SJ Foti as Principal Engineer at Flam & Russell, Horsham, Pa, USA. The antennas operated over a wideband and provided very low side-lobes in the diagonal planes which minimised reflection effects in the vertical and horizontal planes of anechoic chambers.

Emergency Position Indicating Radio Beacon

As Technical Executive, Antenna Systems at ERA Technology, Leatherhead, Surrey, UK, SJ Foti provided consulting services to Clifford & Snell who developed this product.

Printed Meanderline Polariser to convert Linear to Circular Polarisation as a Retrofit to an existing Reflector Feed

Developed by SJ Foti as Technical Executive, Antenna Systems, at ERA Technology, Leatherhead, Surrey, UK.

Novel 'See-Saw' PIN Diode Phase Shifter Provides Conjugate Phase Control of 2-Paths Simultaneously

Developed by SJ Foti when Technical Executive, Antenna Systems at ERA Technology, Leatherhead, Surrey, UK to reduce the cost of a beam scanning antenna. This was one of the key component developments implemented in the TACAN antenna also shown in this gallery.

Wide-Band Butler Matrix incorporating Shiffman Lines

Developed by SJ Foti as Technical Executive, Antenna Systems at ERA Technology, Leatherhead, Surrey, UK. This was one of the key component developments implemented in the TACAN antenna also shown in this gallery. Excellent phase distribution accuracy was maintained by the incorporation of the Shiffman lines.

Scanning Radiometric Medical Antenna System for the Dectection of Skin Cancer

As Technical Executive, Antenna Systems at ERA Technology, Leatherhead, Surrey, UK, SJ Foti led the team in developing this unique system for a customer in the USA. The electro-mechanically scanned reflector antenna was elliptical in shape thus providing a focus at the feed and a focus on the patient's skin. the antenna output was connected to a radiometric receiver to measure the emmissions at 31 GHz.

Underwater Phased Array Antenna System for Medical Diagnostic Imaging

As principal Engineer at Flam & Russell, Horsham, Pa, USA, SJFoti led the team to develop this unique system. This system represented one of the first underwater array antenna systems which achieved much improved coupling between the radiated microwaves and the human body because the high reflections associated with an air-to-body interface were removed.

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