摘要:
A wireless access gateway for communication of wave signals at radio frequencies within a frequency band, includes an access gateway enclosed in a housing including a bottom wall and a main circuit board overlying the bottom wall and having an upper surface substantially parallel to the bottom wall. The gateway is equipped with an antenna system including at least two antennas: a first linearly polarized antenna for propagating a first wave signal along a first polarization axis including a first radiating element extending along a first longitudinal axis lying on a first plane substantially parallel to the base plane, and a second linearly polarized antenna for propagating a second wave signal along a second polarization axis oriented perpendicularly to the first polarization axis, the second antenna including a second radiating element extending along a second longitudinal axis lying on a second plane oriented perpendicularly to the first plane. The first and second antennas are positioned relative to each other at a distance of at least λ/2, where λ is the wavelength corresponding to a radio frequency within the frequency band.
摘要:
A wireless transceiver station including an antenna device and a casing, the antenna device including at least one resonator element cooperating with the casing of the wireless transceiver station and having a shape with a low aspect ratio so as to be conformal with the casing, the at least one resonator element including a composite material and being adapted to be excited by a feed system which is positioned inside the resonator element so as to allow the antenna device to irradiate with a substantially omnidirectional radiation pattern.
摘要:
A wireless transceiver station including an antenna device and a casing, the antenna device including at least one resonator element cooperating with the casing of the wireless transceiver station and having a shape with a low aspect ratio so as to be conformal with the casing, the at least one resonator element including a composite material and being adapted to be excited by a feed system which is positioned inside the resonator element so as to allow the antenna device to irradiate with a substantially omnidirectional radiation pattern.
摘要:
The present invention relates to a method for optimizing the positioning of high sensitivity receiver front-ends 5 in a mobile telephony network 1 of the CDMA type comprising a plurality of cells 2. The method comprises the following steps: defining a first and a second cell indicator Vcell, V2; defining a first and a second threshold value L and L2; comparing said first cell indicator Vcell with a first threshold value L and said second cell indicator V2 with a second threshold value L2; associating with a first category a plurality of first cells 2a having said first cell indicator Vcell greater than said first threshold value L or said second cell indicator V2 greater than said second threshold value L2; positioning a plurality of high sensitivity receiver front-ends 5 substantially in all said plurality of first cells 2a. The method further comprises the steps of: associating with a second category a plurality of second cells 2b having said first cell indicator Vcell smaller than said first threshold value L and said second cell indicator V2 smaller than said second threshold value L2; positioning a plurality of low sensitivity receiver front-ends substantially in all said plurality of second cells 2b.
摘要:
A tunable delay line for radiofrequency or microwave frequency applications consists of at least one ridge waveguide in which the ridge is movable in the waveguide body so as to vary the width of an air gap defined between the longitudinal end surface of the ridge and a confronting member of the waveguide. The ridge is moved by an actuator external to the waveguide body.
摘要:
A sun tracker device includes a base frame provided with a track that is at least in part circular; a support structure, of at least one photoreceiver module, the support structure being slidably associated with the track and including a reference plane for the coupling to the at least one photoreceiver module; a first motor group for controlling the movement of the support structure on the track around a substantially vertical axis; and at least one movement member of the at least one photoreceiver module around a respective substantially horizontal axis. The reference plane is tilted, with respect to a support plane of the device, by an angle of predetermined amplitude. An optimal compromise is achieved between maximisation of the energy yield and minimisation of the device size, at the same time ensuring an easy access to the components of the device for the maintenance operations.
摘要:
A tunable delay line for radiofrequency or microwave frequency applications consists of at least one ridge waveguide in which the ridge is movable in the waveguide body so as to vary the width of an air gap defined between the longitudinal end surface of the ridge and a confronting member of the waveguide. The ridge is moved by an actuator external to the waveguide body.
摘要:
A differential delay element for use, e.g., in selectively delaying RF signals in telecommunication systems includes a first microstrip circuit and a second microstrip circuit arranged side-by-side in a facing relationship. The first microstrip circuit defines a first delayed travel path for a first signal from a first input port to a first output port and the second microstrip circuit defines a second delayed travel path for a second signal from a second input port to a second output port. A perturber is arranged between the first and second microstrip circuits, displaceable toward and away from the first and second microstrip circuits, so that when the distance of the perturber to one of the microstrip circuits increases, the distance of the perturber to the other of the microstrip circuits decreases and viceversa. The position of the perturber between the first and second microstrip circuits defines the differential delay, namely the difference (Δτ=τ1−τ2) between the times (τ1,τ2) experienced by the two signals in travelling their travel paths through the delay device.