Showing papers on "Feed line published in 1984"

Miniature radio transceiver antenna

Abstract: A compact, lightweight, printed circuit card antenna which is adaptable to a wide range of frequencies, including very low frequencies. The antenna includes a three-dimensional inductor formed on the card, a peripheral conductor stripe on one side of the card which provides a distributed capacitance to the end of the antenna (to cancel inductive effects and broaden its bandwidth), and a peripheral conductor on the opposite side of the card which provides a capacitance to ground (to tune the antenna to frequency), and a transmission line feed point which provides an impedance match to the associated printed circuit flat cable transmission line without the use of impedance matching circuits.

Microwave applicator for frozen ground

Abstract: A microwave applicator for heating materials with microwaves. A coaxial transmission line is inserted in the material and coupled at one end to a source of microwaves. A shorting plate covers the other end of the cable and a plurality of radiating apertures are provided along the outer conductor. The use of a coaxial line avoids the minimum size requirements present with hollow waveguides. The coaxial line may be directly coupled to the output probe of a microwave generator by means of spring-finger contacts on the inner conductor of the coaxial line.

Backfire bifilar helix antenna

Abstract: A backfire bifilar helix antenna is disclosed having two helically wound conductors made of coaxial cable wherein the two conductors comprise the shield portion of the cable. The coaxial cable of one of the conductors serves as a transmission line for supplying signals to the feed end of the antenna and has its center conductor connected to the shield of the other conductor cable. The nominal input impedance of the antenna may be adjusted to a desired value by conductive surface layers attached to the shield portion of the conductors at the feed end.

Telescopic antenna extended by coaxial cable feed

Abstract: A plural band telescopic antenna, including an added band much higher than the frequencies of the AM/FM band, is realized by making one telescopic section into a center-fed, high frequency antenna and using its coaxial cable feed line for also coupling mechanical extension and retraction forces to that section.

Instrusion detection system

Abstract: An intrusion detection system that comprises a transmission line for RF energy, a transmitter coupled to one end of the transmission line to supply pulses of RF energy into the line, and a range gated doppler receiver for receiving RF energy from the other end of the transmission line. The receiver includes means for producing a detection signal indicating the presence of doppler components in a range gated portion of the RF energy received from the transmission line.

Analysis of a Suspended Patch Antenna Excited by an Electromagnetically Coupled Inverted Microstrip Feed

Abstract: A suspended patch antenna electromagnetically excited by an inverted micros trip line has been studied based on a full-wave transmission line analysis in conjunction with a microwave network theory. The input impedance calculated has been compared with measured data.

Apparatus for controlling a process variable of a flowing medium

Abstract: The plant has a controlled section through which water flows, for example, for cooling or heating purposes. The operation of the controlled section is controlled by obtaining temperature measurements of the flow via a pair of temperature sensors and emitting a control signal in response to a difference to a valve in a connecting line which is in parallel with the heat exchanger. The same signal is also directed to a comparator in a control circuit within which a second process variable, i.e. flow quantity, is measured. A comparison between these latter signals is made and a resulting difference signal is used by a controller to adjust a valve in the feed line to the heat exchanger to adjust the flow of medium. Should the temperature of the flow downstream of the junction point of the connecting line and heat exchanger increase, the valve in the connecting line is moved in closing direction to increase the flow to the heat exchanger and at the same time, the valve in the feed line is further opened to additionally increase the flow to the heat exchanger. Shortly thereafter, this increase in flow causes the valve in the feed line to be moved back in closing direction.

Mode-controlling waveguide-to-coax transition for TV broadcast system

Abstract: A coax-fed slotted-cylinder (pylon) antenna for UHF television operation at power of 200 kW and above has a coaxial feed which is large enough to propagate higher TE 11 mode as well as the desired fundamental TEM mode The power fed to each slot and as a consequence the antenna array factor may be perturbed by the higher modes It is important to reduce losses in the feed of the high-power signals from the transmitter or high power amplifier up the tower to the antenna For lowest loss, a waveguide is used for the run up the tower A waveguide-to-coax transition is used for adapting the waveguide to the coaxial antenna feed while suppressing the undesired TE 1 ,1 mode The transition has two short semicircular waveguides opening into the waveguide feed from the transmitter The semicircular walls of the two waveguides are coupled to the outer conductor of the coax antenna feed The semicircular waveguides have a common flat wall, the center of one core of which is coupled to the center-conductor of the coax antenna feed

Appliance with a water feed line, especially washing machine, dishwasher or the like

Abstract: In known appliances (G) with a water feed line (L), especially in washing machines, dishwashers or the like, leaks in the appliance (G) entail overflows which may cause damage. In order substantially to prevent this, it is proposed, according to the invention, to arrange in the water feed line (L) a valve (V) which is closed when a moisture sensor (RF) arranged under the appliance (G) is moistened.

Applying CATV technology and equipment in guided radio systems

Abstract: CATV amplifiers, cables and coupling devices have been successfully used in radio signal boosters systems in Canada and Saudi Arabia. The equipment is very reliable and the gasketed housings afford proection from adverse environments. CATV equipment can be used in either leaky cable antenna systems, or in distributed antenna systems consisting of small antennas, spaced as required, and fed by splitters from a trunk line CATV cable. Procedures for making signal quality and signal margin surveys are described, and the design parameters of a large two way signal booster system are explained.

Method and device for testing granular material

Abstract: The method and the device for testing granular material, which is intended for the extrusion of an insulation for cables, provide, in the outlet line (15) from a preparation system (10) or in the feed line (15) to a processing extruder (31), a branch line (16) via which a small proportion of granular material is fed to a measuring extruder (20).

Microstrip antenna with resonator feed

Abstract: An antenna element including microstrip having a microstrip feed line and ground plane on opposite sides of a substrate, a resonator on the same side of the substrate as the microstrip feed line, and a dipole insulated from the feed line and from the resonator.

Bandwidth limitations of log-periodic microstrip patch antenna arrays

Abstract: Results are presented for the frequency dependence of the propagation constant of uniform microstrip patch arrays that allow the bandwidth limitations of log-periodic patch arrays to be deduced. It is found that direct coupling of the patch to the feed line limits the log-periodic bandwidth to about a 2:1 frequency range. However, the introduction of series reactance into the equivalent circuit such as by the use of overlaid patches indicate that log-periodic action over a very wide bandwidth is possible which will then be limited by the uniform substrate and production tolerances.

Process-variable regulating device for a flowing medium

Abstract: not available for EP0149002Abstract of corresponding document: US4702306The plant has a controlled section through which water flows, for example, for cooling or heating purposes. The operation of the controlled section is controlled by obtaining temperature measurements of the flow via a pair of temperature sensors and emitting a control signal in response to a difference to a valve in a connecting line which is in parallel with the heat exchanger. The same signal is also directed to a comparator in a control circuit within which a second process variable, i.e. flow quantity, is measured. A comparison between these latter signals is made and a resulting difference signal is used by a controller to adjust a valve in the feed line to the heat exchanger to adjust the flow of medium. Should the temperature of the flow downstream of the junction point of the connecting line and heat exchanger increase, the valve in the connecting line is moved in closing direction to increase the flow to the heat exchanger and at the same time, the valve in the feed line is further opened to additionally increase the flow to the heat exchanger. Shortly thereafter, this increase in flow causes the valve in the feed line to be moved back in closing direction.

Apparatus for matched impedance feeding of microstrip-type radio frequency antenna structure

Abstract: The center region of a dual slot microstrip-type antenna radiator "patch" structure (12) is forced to take on a controlled non-zero radio frequency impedance by the provision of a slot (20) formed therein at the center region. By controlling the dimension of such an impedance-matching slot in the radiator patch, a feedpoint connection (18) may be made at the center region of the radiator patch and still achieve matched impedance feed. Because the feedpoint can thus be centrally located within the antenna structure, any spurious radiation which occurs from the feedpoint connection or associated feedlines does not tend to skew the overall or composite radiation antenna of the pattern as much as when such feedpoints are asymmetrically disposed on the radiator patch with respect to the primary radiating apertures.

Phase slope equalizer

Abstract: A microwave antenna feed network dispenses with the conventional phase shifters. Instead, the required phase relationships between the different individual antenna components is achieved by means of a new device, known as a phase slope equalizer, placed in each feed line. This device is formed of a section of waveguide containing one or more resonant circuit elements. Each element comprises, for example, a pair of spaced inductive posts and capacitive tuning screw, or an inductive iris and a capacitive tuning screw, or a resonant slot. The phase slope equalizer exhibits a substantially constant slope phase shift/frequency response curve extending from a positive phase shift through zero phase shift at midband to a negative phase shift. The device is simpler and smaller than the conventional phase shifter and fewer are required thereby reducing costs.

An Analysis of the AC Bandwidth of Transmission Line Discriminators for FM Noise Measurement

Abstract: An error in [1] motivated a derivation of the frequency response of transmission line discriminators. The derivation properly handles the limit as f/sub m/ /spl rarr/ 0. Experiments are reported which confirm the DC response of transmission line discriminators and the (sin x)/x shape of the frequency response characteristics.

Arrangement for biasing high-frequency active components

Abstract: An arrangement for applying a DC bias current to an RF active component, such as a field effect transistor, serially-connected with an RF transmission line. The biasing current is supplied by a transmission line section connected at a junction to the transmission line. Two conductive strips, connected in parallel with the transmission line, on opposite sides of the junction, form a band-pass filter. Each of these strips is situated at a distance from the junction which is equal to approximately one-eighth of the wavelength of the signal frequency transmitted on the transmission line.

Installation for cooling a fuel element storage well with several water circuits

Abstract: Installation for cooling a water-filled fuel element storage well, including a plurality of cooling circuits having drain lines with connections to the well, pumps connected to the drain lines, heat exchangers connected to the pumps and feed lines being connected to the heat exchangers and having connections to the well, one of the connections of the drain lines to the well being disposed at a level which is at least as high as the other of the drain line and feed line connections, and a downwardly directed pipe disposed in the storage well being connected to the one of the drain line connections and having a lower opening formed therein at a lower level than the drain line and feed line connections.

Method for transmitting character code

Abstract: PURPOSE:To reedit automatically a format into a format requested by a receiving side, by performing the processing where a line feed control code in a document is eliminated at the transmission side and the feed line conrol code is inserted newly at each number of characters determined with the standard format. CONSTITUTION:The communication mode and the format and the like are determined with the negotiation with an opposite terminal bofore the transmission of sentence forming information. When the transmission is attained with the change from the option mode into the standard mode, the communication is attained via a conversion processing section 11. The control code for line feed not required for the document formed with the format in the option mode is eliminated, and the line feed control code is inserted newly at each character number determined with the format in the standard mode after alteration.