Abstract: A circular polarized array antenna includes: groups of at least one set of patches for radiating and/or receiving a circular polarised electromagnetic wave; and a network of feeding lines, each feeding line being coupled to and extending longitudinally or vertically to one of the sets for transferring signal energy to and/or from the set. Each of the feeding lines coupled to the sets is pointing into a direction different from the pointing direction of the other feeding lines in order to achieve a circular orientation of the network of feeding lines.

Abstract: The present invention provides a short-range wireless mobile communication system with a first terminal (1) and a mobile terminal (2) that are each adapted for transmitting and receiving an information carrying signal wave, whereby at least the first terminal (1) or the mobile terminal (2) comprise a directional signal wave converter (1a) for transmitting and/or receiving the information carrying signal wave with a directional characteristic (1bI, 1bII) and a control means (4, 5, 20) for controlling the directional characteristic (1bI, 1bII) according to a position of the mobile terminal (2) relative to the first terminal.

Abstract: The invention relates to a wireless optical data transmission system and a method for wireless optical transmission of data. The system comprises a data stream generator for generating at least two parallel data streams (18.1, 18.2, 18.3). The parallel data streams are transmitted by a number of separate optical transmitting devices (8, 9, 10) separately by emitting first optical signals. The system further comprises a corresponding number of detectors (19, 20, 21) for detecting the first optical signals and converting them into respective second signals (26.1, 26.2, 26.3) and an error correction unit (31) for correcting the amended second signals. Within a predistortion (29) unit each second signal (26.1, 26.2, 26.3) is amended individually with respect to a transmission channel used.

Abstract: The present patent application is directed to a communication system 0 comprising a first station 1 with a first narrow beam antenna 31 and a second station 2 comprising a second narrow beam antenna 41, wherein the first and second stations 1, 2 are adapted to establish a first communication path 7a for wireless communication via said first and second narrow beam antennas 31, 41, respectively. It is a disadvantage with such a communication system that communication via said first communication path might be disturbed by randomly appearing obstacles. In consequence, the data transmission rate is reduced. According to the present invention said first and second stations 1, 2 are adapted to automatically establish at least one alternative communication path 7b, 7c for wireless communication via said first and second narrow beam antennas 31, 41, said alternative communication path 7b, 7c being spatially different from said first communication path 7a.

Abstract: The present invention relates to a frequency-shift-keying demodulator (1, 1?) comprising a phase shifter 2 for shifting the phase of an input signal i(t) by a predetermined degree and for outputting a shifted signal Id(t), a combining unit (3, 4; 31, 32, 33, 41, 42) for combining the input signal i(t) and the shifted signal Id(t) output by the phase shifter 2 and for outputting a corresponding signal r(t) and a low-pass filter 5 for filtering the signal r(t) output by the combining unit (3, 4; 31, 32, 33, 41, 42), and for outputting a low-pass filtered signal rLP(t) the bandwidth of said low-pass filter 5 being matched with the bandwidth of a data signal contained in said input signal i(t).

Abstract: The present invention relates to a circular polarised array antenna comprising groups of at least one set of patches for radiating and/or receiving a circular polarised electromagnetic wave, a network of feeding lines, each feeding line being coupled to and extending longitudinally or vertically to one of the sets for transferring signal energy to and/or from the set whereby each group of feeding lines being coupled to a group of sets is pointing into a direction different from the pointing direction of the other groups of feeding lines in order to achieve a circular orientation of the network of feeding lines and respectively two adjacent groups of feeding lines include the same angle. The invention further relates to a method for executing the steps on the array antenna, to a beam-switching array antenna and to a method for a beam-switching array antenna.

Abstract: Apparatus for carrying out correction of a received frequency at a time of receiving a digitally modulated signal includes a phase judging circuit for judging a phase of a received signal symbol in terms of a predetermined number of quantization, a phase difference detecting circuit for detecting a phase difference between phase judged samples judged by the phase judging circuit and an averaging circuit for averaging a detecting output of the phase difference detecting circuit, whereby it is possible to control an output frequency of a frequency synthesizer based on the averaging circuit output.

Abstract: The underlying invention generally relates to the field of wireless communication systems with high-speed mobile access, especially to Orthogonal Frequency Division Multiplexing (OFDM) systems considering channel estimation and/or channel tracking. More particularly, the invention provides an adaptive subcarrier loading function for a mobile receiver (1310) in a wireless communication system based on OFDM that can advantageously be applied to predict the channel transfer function H(j·&ohgr;,t) of a multipath propagation channel (1320) being severely impaired by frequency-selective fading and an extremely time-variant behavior by detecting the position and/or movement of zero points (A, B, and C) of said transfer function H(j·&ohgr;,t), thereby reducing the probability of an incorrect assignment of the modulation scheme for each subcarrier (102), that is caused by mobile terminals (405) moving at high velocity.

Abstract: A demodulating apparatus that can reduce power consumption significantly compare to conventional cellular phones without the reception quality being degraded. Delay profile measuring is provided in which the delay profile (S41) of the baseband signal is measured while changing the measuring time for measuring the delay profile of the baseband signal, so that the measuring time can be held down to a minimum while avoiding the degradation of the reception power level. Therefore, power consumption can be significantly reduced compared to conventional cellular phones without reception quality being degraded.

Abstract: An infrared gas analyzer is formed of a source of infrared rays for emitting infrared flux; an infrared flux interrupting device for chopping the emitted infrared flux from the source of the infrared rays; a condensing optical system for obtaining a predetermined solid angle in the emitted infrared flux to thereby form a condensed flux; and a multi-reflection cell disposed at an outlet of the condensing optical system, to which the condensed flux is supplied and a gas to be measured is fed. The multi-reflection cell has a multi-reflection optical system formed of a plurality of concave mirrors. The analyzer also includes an infrared level detector for detecting an amount of infrared rays with a wavelength band absorbed by a component gas to be analyzed and contained in the infrared rays emitted by the multi-reflection cell.

Abstract: In an infrared radiation source containing hot-pressed molybdenum disilicide reinforced with silicon carbide whiskers as the illuminant thereof, terminal portions of the illuminant having a protective dense silica film of 5 to 20 .mu.m in thickness formed on the surface thereof which portions are to be heated at a temperature of 400 to 800.degree. C. are either set to have a current density of at most 12 A/mm.sup.2 or disposed in dry air having a relative humidity at 25.degree. C. of at most 30% (absolute humidity: 0.00588). As a result, the low-temperature oxidation phenomenon that would otherwise be developed in the terminal portions of the illuminant is suppressed. Thus, there can be obtained an infrared radiation source containing an illuminant made of molybdenum disilicide reinforced with silicon carbide whiskers and having a long serviceable life span.

Abstract: A ceramic heating element includes a heat-generating portion 1 formed of a ceramic composite material with 3 to 40 vol. % of silicon carbide (SiC) whiskers and the balance substantially of molybdenum disilicide (MoSi.sub.2), and electrode portions 2a and 2b provided on both ends of the heat-generating portion 1.

Abstract: A ceramic heating element has been conventionally driven by direct-current voltage, but the direct-current voltage causes a problem in the heating element. Therefore, in a method of the present invention, an alternating current is supplied to the heating element by changing a direct current, so that deformation of the heating element can be prevented and reliability can be improved.

Abstract: A variable gain amplifier of a transmitter is controlled to obtain optimum transmission power by using a directional coupler and a detector to detect the transmission signal level that is then subtracted from a reference signal corresponding to a desired transmission signal power. The subtracted output is used to control the variable gain amplifier. The reference signal is generated by a control circuit and a digital-to-analog convertor that produce an attenuated basic reference signal. The attenuated basic reference signal is further adjusted in signal level by a voltage divider network that is controlled by a number of control signals produced by the control circuit.

Abstract: A detector for an infrared gas analyzer is formed of first and second light receiving rooms filled with gas to be analyzed, a gas passage communicating between the first and second light receiving rooms, and a heat-sensitive resistance element disposed perpendicularly to the gas passage. The heat-sensitive resistance element includes at least one heat insulator having an opening at a center thereof, a pair of heat-wire elements disposed on the heat insulator to face against each other with a predetermined space therebetween, and a heating device. Each heat-wire element has a plurality of elongated elements disposed parallel to each other in the opening of the heat insulator, and connecting portions for connecting ends of the elongated elements for serially connecting the elongated elements. The heating device is formed on the heat insulator around the opening to equalize temperature in a space surrounded by the heat-wire elements in the opening. Accordingly, the analyzer can be operated stably.

Abstract: A sample cell of the multiple reflection type is used for analyzing a sample in the same cell. In the sample cell, incident light is reflected a plurality of times. The sample cell includes a mirror plate including a light incident window for introducing the incident light into the sample cell, a first concave mirror, and a light exit window for outputting the incident light form the sample cell. A side plate including a second concave mirror reflects the incident light to the first concave mirror and a third concave mirror for reflecting the incident light reflected by the first and second concave mirrors to the light exit window. The cell also includes a frame for fixing the mirror plate and the side plate so that the distances between the first concave mirror and the second and third concave mirrors are fixed at a distance equal to the radius of curvature of the three concave mirrors.

Abstract: An infrared gas analyzer, of compact and inexpensive design, has improved detection sensitivity. The infrared gas analyzer includes an infrared radiation source, a measuring cell, a reference cell, and a detector. The detector includes two detector cells in which the same species of gas, as the gas to be analyzed, is enclosed. A gas flow channel connects the detector cells to each other. Two thermal sensors are disposed in the gas flow channel, each of which further includes pairs of thermo-elements. The thermo-elements are arranged in such close proximity to each other, as to originate a thermal coupling between the pairing elements, and the thermo-element pairs are separated by a distance across which thermal coupling between the thermo-element pairs becomes insignificant. The detector detects, by the thermal sensors, a gas flow indicative of infrared absorption intensity difference between the measuring and reference cells.

Abstract: A non-dispersive infrared gas analyzer, with improved linearity in output concentration signal especially in measuring gas species of high concentration, includes a measuring cell into which a gas to be measured is fed, a non-selective infrared radiation sensor disposed on one side of the measuring cell, an optical band-pass filter disposed between the measuring cell and the infrared radiation sensor, and a nonselective infrared radiation source, disposed on the other side of the measuring cell and having an infrared radiation transmission window, wherein the radiation source further includes a gas filled therein at a predetermined partial pressure and the filled gas has at least a common partial molecular structure with the gas to be measured.

Abstract: An eject mechanism for ejecting automatically the tape cassette in a tape player, in which one of two switching gears disposed on both the sides of a gear plate and engaging with a forward/backward rotating gear is selectively engaged with an intermittent gear by said forward/backward rotating gear and said intermittent gear drives the driven mechanism for the eject operation, said intermittent gear being so constructed that it is locked only in the forward rotational direction.

Abstract: An optical gas densitometer is provided comprising a conical filter portion having a front and rear end disposed to the inside of a cell portion and formed into a conical shape, which has a reflection mirror disposed to the inside of the front end thereof, windows disposed at the rear end thereof and in which the angle between an incident optical beam and an exiting optical beam is predetermined. Plate means at the front end of the filter and formed in a space between the inside of the cell portion and the outside of the conical filter portion, divides the space into a gas feed channel below the plate means and a gas exhaust channel above the plate means. An opening channel is disposed between the gas feed channel and the gas exhaust channel towards the rear end of the filter. A partition plate connected to the plate means at the front end of the filter, divides a gas sampling tube into first and second channels which correspond to the feed channel and exhausting channel, respectively.