LEA64A~1 by ruben reyes

Electron B4540

S.R.L.

Design Production & Trading of Educational Equipment

MICROWAVES TRAINER

ELECTRON S.R.L. VIA CASCINA TORCHIO I-26833 MERLINO (LO) - ITALY TEL. 39(Italy) 02(Milan) 9065 9200 FAX 9065 9180 - E-mail: electron@electron.it Web: www.electron.it Rev 08/00 Specifications may change without notice

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File LEAFLET B4540

B4540 – MICROWAVES TRAINER

General:

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The B4540 trainer is a module-composable laboratory unit aimed to the following major topics:

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To teach the fundamentals of microwave circuits. To execute basic measurements and experiments. To familiarize the student with the construction characteristics of microwave components and the architecture of microwave systems.

The trainer consists of two sections, the first of which includes components to set-up the MW laboratory bench to study the MW circuits. The second section deals specifically with microwaves antennas and is aimed to experiment the aspects of microwave transmission and reception in the open space. This second section of the trainer is not a self-standing unit but should be regarded as an appendix or expansion of the first.

Study topics: – –

Techniques of microwave generation. Propagation of microwaves into waveguides and coax cable.

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Measurements of wavelength. Standing Wave Ratio and Impedance matching. Attenuation techniques and measurements. Microwave data links

The second section of the trainer, focused on antennas and propagation, uses several components of the first one to set-up a transmitter-receiver test system. The major types of antennas can be tested and studied, and their radiation patterns recorded. These include horns, parabolic and slot array antennas. The construction of the trainer, in both the first as well as the second section closely reflects the most advanced principles and industry-level standards. In addition facilities are foreseen to set-up actual transmission links for complex demonstrations involving other teaching equipment from our range. The trainer comes complete with a CD containing support software (2-pcs required) for digital data transmission Operation of the trainer is in the range of 10GHz. Power supply is from AC mains at 110-240V AC, 50 or 60Hz.

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File LEAFLET B4540

The following is a complete list of the components available with the training system. The components marked (B) are included in the Basic trainer configuration. The components marked (E) are added to provide an Expanded trainer configuration. The components marked (O) (O are Optionals which can be provided to fulfil specific training requirements.

(B) (B) (B) (B) (B) (B) (B) (B) (B) (B) (B)

1 pc 1 pc 1 pc 1 pc 1 pc 1 pc 1 pc 2 pcs 1 pc 1 pc 1 pc

Microwave generator, 10.7GHz, +7dBm with ASK modulator Fixed attenuator, -6Db Variable attenuator, flap type, -20dB Cavity wave meter Slotted line detector Slotted line tuner Detector diode assembly (WG) Matched terminations Shorting plate Directional coupler, cross type, -20dB Auxiliary module with power supply and detector signal conditioner/ meter (B) 1 pc Signal amplifier (B) 1 pc Digital Data Link Receiver (DDLR) (B) 1 pc Software package for Microwave data link demonstration (B) 1 pc Moving target (fan) for Doppler experiments (B) 1 pc Support for moving target (B) 1 pc Set of base stands (3 pcs each trainer) (B) 1 pc Set of power and measurement cables (B) 1 pc Component case (O) 1 pc Additional component case for Optional and Expansion components (B) 1 pc Set of assembly screws and nuts (B) 1 pc Set of fast assembly clips (E) 1 pc Isolator (O) 1 pc Circulator (B) 2 pcs Horn antennas, small (O) 2 pcs Horn antennas, large (E) 1 pc Parabolic antenna with feeder (E) 1 pc Slot array antenna (E) 1 pc Base support for antennas, rotating, with protractor (E) 1 pc Base support for antennas, fixed (E) 1 pc Fixing clamp for parabolic antenna (E) 1 pc Fixing clamp for slot array antenna (E) 1 pc Fixing clamp for horn antenna (E) 1 pc Shunt (H plane) tee (E) 1 pc Series (E plane) tee (O) 2 pcs Waveguide-to-coax cable transitions (O) 1 pc Microwave cable ELECTRON S.R.L. VIA CASCINA TORCHIO I-26833 MERLINO (LO) - ITALY TEL. 39(Italy) 02(Milan) 9065 9200 FAX 9065 9180 - E-mail: electron@electron.it Web: www.electron.it Rev 08/00 Specifications may change without notice

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File LEAFLET B4540

(O) (O) (O) (O) (O) (O) (O) (O)

1 pc 1 pc 1 pc 1 pc 1 pc 1 pc 1 pc 1 pc

(O) 1 pc (O) 1 pc (O) 1 pc (O) 1 pc (O) 1 pc (O) 1 pc

Coax detector Pin modulator Straight waveguide, 100mm 3-screw transformer Phase shifter DC blocker Set of 4 diaphragms with slits Holder for material samples and Material samples (polystyrene and non-magnetic absorber material) Moveable short Set of WG propagation accessories (5 WG diaphragms with circular apertures 10, 9, 7, 6, 0 mm diameter) Set of Physics MW accessories (4 plates, 230x230; Alu sheet, grilled PCB, foam material, dielectric) Support for MW accessories E-field probe Spare MW detector diode 1N123N

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File LEAFLET B4540

Description of the major components of the B4540 trainer. B4540B4540-B1 – Generator: A new era in low-cost, ultra-stable microwave generators has resulted from the use of solid state devices. The type of oscillator provided with the B4540 trainer is based on a dual-gate Mesa field effect transistor. This type of oscillator has the advantage of high efficiency from low-power drain and small size. The technical characteristics are as follows: – – –

frequency of operation: 10.75GHz power supply: 12 V, 100mA output level : +7dBm

B4540B4540-B2 – Fixed attenuator: This component basically consists of a trunk of straight waveguide with a thin layer of conducting absorber inserted along the main symmetry plane of the guide. The absorbing material draws power from the travelling wave and converts it into heat. Therefore the signal level is lowered by an amount which is fixed, being determined by the shape, size, position of the absorber.

B4540B4540-B3 – Adjustable attenuator: An absorbing material is mounted on a movable flap. The flap is adjusted in or out of the wave guide of any amount desired, thus giving total freedom of adjustment. The maximum attenuation allowed by the variable attenuator of the B4540 is approx. 24dB. Note: This component is often referred to as a Flap Attenuator, Rotary Vane Attenuator, etc..

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File LEAFLET B4540

B4540B4540-B4 – Matched termination: The matched termination is essentially a matched load to the microwave transmission line. Its function is to absorb all the energy incoming from the wave guide. A perfect match implies that no EM energy is reflected back towards the source, thus the Standing Wave Ratio in a system is minimized.

B4540B4540-B5 – Cavity wave meter: The device basically consists of a cavity coupled to a trunk of straight wave guide by a calibrated slot in one of the WG walls. The effective size of the cavity is made variable by moving in and out a piston by means of a dial knob assembly. When the resonance frequency of the cavity is equal to the frequency of the signal in the wave guide, there is a maximum of energy transfer from the wave guide to the cavity. It is therefore possible to use the adjustablecavity resonator as a frequency meter by calibrating the dial indicating the position of the piston.

B4540B4540-B6 – Slide screw tuner: Its function and principle of operation are as follows: the field pattern inside a guide can be modified (adjusted) to some extent by tuning devices, the simplest of which is a simple screw or pin in a wall. The depth of the screw inside the guide determines the amount of field modification. The adjustment range increases if the pin is placed where the field is more intense. The mechanical structure of the slide screw tuner consists of a pin mounted on a carriage which slides along a long slot of the feeding wave guide. This can be used to match loads to the characteristic impedance of the wave guide, thus reducing the SWR.

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File LEAFLET B4540

B4540B4540-B7 – Slotted line detector: It basically consists of a sliding carriage like the screw tuner already seen, with the difference that the probe is now connected to a crystal detector. In measuring the standing wave inside a wave guide, a slotted line is used to probe the amplitude and the phase of the standing wave pattern. Obtaining the standing wave pattern information allows us to determine the wavelength, standing wave ratio and the impedance of the transmission line. Each time the slotted line is being used within a microwave circuit the depth of the probe should be adjusted for the best performance.

B4540B4540-B8 – Crystal Detector: The crystal detector is located inside a short wave guide segment. The crystal detector is basically a diode assembly which responds to the electromagnetic field inside the wave guide. Since an RF voltage is being induced across the diode by the electromagnetic wave, the diode can be used for detection of microwave energy.

B4540B4540-B9 – Shorting plate: plate: When executing certain experiments it is desirable to terminate the wave guide, on the side opposite to the generator, with a termination that at least theoretically completely reflects the travelling wave (zero impedance). Such a termination is physically realized with a small plate of conductive material.

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File LEAFLET B4540

B4540B4540-B10 – Directional coupler: The directional coupler is basically a 4-port device, which allows directional coupling of energy in the wave guide. A directional coupler is made of two wave guides combined together and coupled by holes at the joining section of the two. Directional couplers are basically used as sampling devices for the microwave signal. For instance they can be used in microwave systems where measurements of incident and reflected power are needed to determine the Standing Wave Ratio or SWR. The directional coupler of the trainer has a 20dB coupling factor and a directivity of approximately -40dB.

B4540B4540-B11 – Auxiliary module The auxiliary module groups the facilities required for execution of the experiments.

Features: – – – –

AC 220V mains powered (other supply voltages available on request). Power Supply for the MW generator, at 12V, stabilized. The power source is short-circuit protected Detector signal amplifier and meter, with range selector Signal generator, amplitude-adjustable, for use as a source of modulating signal for the microwave.

B4540B4540-B12 – Signal amplifier: The signal amplifier is used within the trainer to reinforce the detector signal whenever this is too weak to be easily observed and measured. The signal amplifier is enclosed in a compact metallic enclosure provided with BNC input and output connectors. The signal amplifier provides DC amplification x 100 and x10000. It requires a symmetrical and stabilized power supply of +12 and -12V (+15 and 15V max).

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File LEAFLET B4540

B4540B4540-B13 â&#x20AC;&#x201C; Horn antenna (small): Horn antennas can be regarded as the simplest means of coulpling a wave guide circuit to the open space. In addition to matching the impedance and reducing the SWR to an acceptable level, the flare offers good directivity gain, a narrower beam width angle and simple construction. In addition, because there are no resonant parts, the horn antenna will cover a wide frequency range.

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File LEAFLET B4540

Components of the extension extension and optional kits (to be ordered separately) B4540B4540-E1 – Isolator (extended) B4540B4540-O1 – Circulator (optional): Isolators (E1) and circulators (O1) are strictly related devices. These are 3-port devices. The signal entering the circulator from A leaves the device at B and (ideally) none of this power reaches C. The power coming from B goes all (ideally) to C, while none reaches A. Circulators are often used within microwave systems, for example, a Radar system where A is the transmitter, B the antenna and C the receiver. The isolator is a circulator with a matched termination on port C. It can be used for instance to isolate a stage from the power reflected by a possibly mismatched load.

B4540– B4540–E2 – (extended):

Parabolic

antenna

The parabolic antenna consists of a parabolic reflector and a feeder. This type of antenna is very common in microwave communications. The parabolic reflector is illuminated by a wave guide rear feed. The feeder is fastened to the dish by inserting it through a hole in the rear of the dish and then fixing it with four screws. The parabolic antenna is supplied with a vertical desk-top stand, allowing the adjustment of the angular position of the antenna.

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File LEAFLET B4540

B4540B4540-E3 – Slot array antenna (extended): This type of microwave antenna is very useful for vehicular application, where it is often important that the antenna does not protrude from the surface. Several slots are made in the same wave segment, at such a distance to guarantee phase-coherence of the waves radiated by each slot. The total wave is therefore reinforced by the contribution of radiation from each slot.

B4540(E--plane) tee B4540-E5 – Series (E (extended) B4540B4540-E6 – Shunt (H(H-plane) tee (extended): Tees are used within a microwave circuit to divide the RF power and connect different items. As in low-frequency circuits, there are two ways in which two single-port devices can be connected into a circuit, i.e. in series or in parallel. The two cases correspond in MW circuits to the two types of Series and Shunt joints. The Series and Shunt Tees are often referred to as “E-plane Tee” and “H-plane Tee”, depending on which flank of the waveguide is used to derive the third leg.

B4540B4540-O2 – Horn antenna (large) (optional): Horn antennas can be regarded as the simplest means of coulpling a wave guide circuit to the open space. In addition to matching the impedance and reducing the SWR to an acceptable level, the flare offers good directivity gain, a narrower beam width angle and simple construction. In addition, because there are no resonant parts, the horn antenna will cover a wide frequency range. The large horn antenna compared to the smaller version offer higher gain and directivity.

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File LEAFLET B4540

B4540B4540-O3 – WaveguideWaveguide-toto-coax transitions (optional): The WG/coax transition provides a match between a waveguide and a coax cable. The operation of the transition is bidirectional. Two of these items, together with a coax cable approx. 30cm long, are provided as optionals, to be used as a flexible connection within a MW circuit.

B4540B4540-O4 – Coax detector (optional): The basic trainer already includes a Detector for waveguide. This second device monitors the WG/coax transition provided and constitutes therefore an interesting experimenting alternative to the first device.

B4540B4540-O5 – PIN modulator (optional): The PIN modulator assembly consists of a PIN diode matched to a short trunk of a waveguide. This mounting arrangement is very similar to that of a Diode Detector. Both the Crystal detector of the basic trainer and this PIN modulator can work as detectors AND Amplitude Modulators. The PIN modulator presents a high reflection when the diode is biased positively and a low insertion loss when biased negatively. By applying a modulated signal to the diode, AM modulation can therefore be obtained.

B4540B4540-O7 – Straight wave guide (optional): This is simply an extension waveguide of length 100mm.

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File LEAFLET B4540

B4540B4540-O8 – 3-Screw transformer (optional): The 3-screw transformer is a trunk of a waveguide with 3 probes. The insertion depth can be adjusted by screws regulators. The probe elements are carefully-set in positions which allow the use this device as a matching element for loads (example: antennas) or to create mismatching for test purposes.

B4540B4540-O9 – Phase shifter (optional): The phase shifter consists of a block of dielectric material, with specific dimensions, mounted in front of the small horn antenna so as to cover one half of the radiating surface. The wave portion travelling through the dielectric will undergo a calibrated phaseshift (180°) with respect to the wave portion travelling in the air, this thanks to the carefully set thickness of the block and its dielectric constant value. The result is that the effects of the two waves will cancel and no signal will be detected in the direction of the main propagation axis. At specific propagation angles from that of the major axis, interference fringes will be observed.

B4540B4540-O10 – DC blocker (optional): The DC blocker is a sandwich-like arrangement of WG flanges with insulating material in-between. It is sometimes used to insulate different trunks of waveguide circuits to DC for the purpose of allowing improved noise-free measurements.

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File LEAFLET B4540

B4540B4540-O11 – Set of 4 diaphragms with slits (optional): (optional): This set of devices is used to study and experiment the radiation properties of slits carved into diaphragms which are mounted as waveguide terminations (diffraction). The list of these items is the following: – – – –

1 diaphragm with slit 2 x 1 diaphragm with slit 2 x 1 diaphragm with slit 2 x 1 diaphragm with slit 2 x

10mm, 0° 10mm, 90° 15mm, 45° 15mm, 90°

B4540B4540-O12 – Holder and material samples (optional): This consists a holder which accepts material samples which are provided with the kit. (Polystyrene and non-magnetic absorber material).

B4540B4540-O13 – Movable short (optional): This consists of a plunger which can move along the major axis of the closed waveguide. The position of the device in the wave guide, can be measured using the micro-meter. This component provides an effective reflection of the incident wave. The movable short is especially recommended for accurate phase and SWR measurements. This component, coupled to a diaphragm can make up a variablegeometry cavity for investigating resonance.

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File LEAFLET B4540

B4540B4540-O14 – Waveguide propagation accessories (optional): (optional): This consists of a set of 5 diaphragms matching the waveguide flanges: – – – – –

1 – Short circuit plate 1 – Diaphragm with 6mm circular hole 1 – Diaphragm with 7mm circular hole 1 – Diaphragm with 9mm circular hole 1 – Diaphragm with 10mm circular hole

These devices can be used as radiating terminations for waveguide circuits. The relevant impedance and radiation characteristics can be studied. Another use is in connection with the movable short to make up a resonating cavity.

B4540B4540-O15 – Set of Physics micromicrowave accessories (optional): This set consists of a series of sheets of various absorbing/reflecting materials, for carrying out experiments of wave attenuation, reflection, polarization and diffraction. The kit includes: – – – –

1 damp foam material plate 1 dielectric plate, PVC 1 metal plate, Aluminium alloy 1 polarization grille on fibreglass substrate.

B4540B4540-O16 – E-Field probe It consists of a Microwave Dipole mounted on the top of a stick incorporating a coaxial drop to the detector diode mounted in the base. This component is used for point by point investigation of the radiation pattern of antennas or of waveguide trunks terminated by radiating diaphragms. The signal output of the E-probe should be connected to the Signal Amplifier included in the basic component kit.

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File LEAFLET B4540

B4541 – MICROWAVE OPTICS TRAINER

This trainer, although designed as an independent teaching unit, can be regarded as an appendix or extension of the B4540 microwave trainer on the subject of unguided microwave propagation and microwave optics. For a clear view, a summary of the B4540/41 trainers organization is as follows: B4540--B – Basic or fundamentals B4540 microwave and microwave circuits

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The major study topics allowed by the B4541 trainer are: –

B4540--E – Expansion Kit to microwave B4540 antennas and antenna-related topics B4540--O – Optional microwave compoB4540 nents and industry-standard MW devices B4541 – Unguided microwave propagation (free-space) and microwave optics The B4541 includes a microwave transmitter (X Band) and receiver, both of a compact and rugged construction and provided with matching horns (pyramidal) and base stands. In addition the trainer includes: –

Meter suitable for connection to the MW receiver

Set of microwave propagation accessories: reflective plate, polarization grille, absorbing material, semitransparent mirror (hardboard) Set of plates with holes/slits to study specific microwave effects such as interference and diffraction. Compact power supplies

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Microwave transmission in the open space Wave polarization Signal transmission/reception, power measurements The principles of MW antennas, Radiation diagrams Stationary waves Reflection – The Brewster angle Diffraction – The Braggs law Interference – Michelson and FabryPerot interferometers Fresnel lenses – Fresnel interferometer

The trainer is of a rugged construction and safe use. It can be easily expanded with items and experimenting devices engineered by the Instructor and/or the students. Ordering code: B4541

ELECTRON S.R.L. VIA CASCINA TORCHIO I-26833 MERLINO (LO) ITALY - TEL. 39(Italy) 02(Milan) 9065 9200 FAX 9065 9180 - E-mail: electron@electron.it Web: www.electron.it Specifications may change without notice

Rev 02/04