|| List of recent Optical Amplifier-related patents
| Optical amplification stage for otdr monitoring and related method and system for otdr monitoring of an optical communication link|
Optical amplification stage (1) for otdr monitoring, comprising a first (2a) and a second optical signal path (2b), a first (3a) and a second optical amplifier (3b), a first optical coupler (4a) placed along the first optical signal path downstream the first optical amplifier, a second optical coupler (4b) placed along the second optical signal path downstream the second optical amplifier, an optical by-pass path (5) optically connecting the first and the second optical coupler, a first (11a) and a second optical reflector (11b) optically connected to respectively the first and second optical coupler, and an optical filter (10) placed along the optical by-pass path which has attenuation high on the whole wdm band and low at the otdr wavelength(s).. .
|Systems and methods for amplifying light|
The invention relates to optical system including light sources that amplify light using a gain medium. Systems and method of the invention are provided for amplifying light while inhibiting reflections at a peak gain of the gain medium, thereby suppressing parasitic lasing.
|Path selecting method and apparatus|
Embodiments of the present invention disclose a path selecting method and apparatus. The method includes: computing an end-to-end path for a newly added service according to network topology and a wavelength constraint, and assigning a wavelength to the path; computing performance of each existing service and performance of the newly added service in a network according to physical impairment information collected in the network, where the physical impairment information includes a gain reference spectrum of each optical amplifier in the network; and performing impairment check on performance of each service, and performing path selection for the newly added service according to a result of the impairment check.
|Optical amplifier device|
An optical amplifier device comprising an input/output section that inputs incident light and outputs emission light; a polarized light splitting section that causes a polarized light component of the incident light input from the input/output section to branch, and outputs first polarization mode light having a first polarization and second polarization mode light having a second polarization different from the first polarization; a polarization converting section that receives the first polarization mode light, converts the first polarization to the second polarization, and outputs first polarization converted light; and an optical amplifying section that amplifies the first polarization converted light input to one end of a waveguide, outputs the resulting amplified first polarization converted light from another end of the waveguide, amplifies the second polarization mode light input to the other end of the waveguide, and outputs the resulting amplified second polarization mode light from the one end of the waveguide.. .
|Method and system for operating semiconductor optical amplifiers|
Disclosed are systems and methods for using a semiconductor optical amplifier (soa) as an optical modulator for pulsed signals. In accordance with the principles of the invention, the soa can be biased with a negative voltage to suppress transmission and improve modulator extinction and biased with a positive pulsed signal with sufficient amplitude to forward bias the amplifier (soa), both transmitting the carrier and increasing its amplitude by means of a gain provided by the soa under forward biased conditions.
|Passive optical networks|
Optical transmitter apparatus 10 comprising a reflective optical amplifier 12, a driver 14, an optical splitter 16, polarisation compensation apparatus 18 and an optical router 20. The reflective optical amplifier is arranged to receive an optical seed signal.
|6x28-gbaud few-mode fiber recirculating loop transmission with gain-equalized inline few-mode fiber amplifier|
Disclosed herein are methods, structures and systems for few-mode fiber (fmf) transmission including an optical amplifier exhibiting modal gain control suitable for such transmission in which higher order modes are amplified. An exemplary evaluation system is described and results presented..
|Integrated laser and modulator transmitter for catv applications|
A cable television (catv) optical transmitter includes a tunable laser having a phase bias input and a gain bias input. The tunable laser generates an optical beam at an output.
|Linecards with pluggable interfaces for pluggable optical amplifiers and other pluggable devices|
A linecard includes at least one pluggable device, a linecard processor, and a centralized host processor. The linecard also includes an interface that supports a pluggable device.
|Optical semiconductor device|
An optical semiconductor device includes: semiconductor lasers separated into two groups; an optical coupler combining light output from the semiconductor lasers; an optical amplifier amplifying light output from the optical coupler; and waveguides respectively connecting the semiconductor lasers to the optical coupler. Each of the waveguides includes a respective bent waveguide.
|Optical amplifier and process|
An optical amplifier receives a seed laser having a wavelength of 1064 nm. Amplification occurs in a segmented nd:yvo4 gain medium pumped with a pump source.
|High-powered optical module safety systems and methods|
A method, optical module, and optical amplifier are configured to detect fiber discontinuities at or near a port from which high powered optical signals are input into a fiber span. These fiber discontinuities can include fiber pinches, and are detected by monitoring for slight changes in a backscatter signal.
|Pulse light source|
The pulse light source comprises a semiconductor laser outputting pulse light, an optical filter, and an optical amplifier. The optical filter outputs a chirping component of the inputted pulse light, by adjusting a relative position of a transmission spectrum of the optical filter with respect to an output spectrum of the seed light source..
|Ultraviolet fiber laser system|
Laser master oscillator-power amplifier system for generating high pulse energy, high average power laser pulses in the ultraviolet 191.25-201.25 nm and 243-246.25 nm spectral ranges, and in the visible 450-537.5 nm spectral range with controllable pulse duration and pulse repetition rate employ a master oscillator seed laser operating in the infra-red spectral range, and a single series connected chain of hybrid fiber-bulk optical amplifiers coupled to a non-linear frequency conversion unit to convert the laser pulses to the ultraviolet and visible spectral ranges.. .
|Tunable system for generating an optical pulse based on a double-pass semiconductor optical amplifier|
A system for generating a shaped optical pulse is disclosed. The system includes a master oscillator for generating an initial optical pulse, which is then directed to a semiconductor optical amplifier to amplify a portion of the initial optical pulse.
|Controller which controls a variable optical attenuator to control the power level of a wavelength-multiplexed optical signal when the number of channels are varied|
An optical amplifier which amplifies a wavelength division multiplexed optical signal having a variable number of channels associated with different wavelengths and outputs the amplified wdm optical signal. The optical amplifier includes a first optical amplifier which amplifies the wavelength division multiplexed optical signal and outputs the first optical amplifier amplified wavelength division multiplexed optical signal; a variable optical attenuator which controls a level of the first optical amplifier amplified wavelength division multiplexed optical signal and outputs the controlled wavelength division multiplexed optical signal; a second optical amplifier which amplifies the controlled wavelength division multiplexed optical signal and outputs the amplified, controlled wavelength division multiplexed optical signal; and a controller which controls the wavelength division multiplexed optical signal to be amplified with a constant gain..
|Optical amplifier, optical amplifying system, wavelength converter, optical amplification method, and optical communication system|
An optical amplifier includes an optical gain fiber into which signal light and pump light are input and at least one relative phase shifter is inserted. Preferably, the relative phase shifter is inserted so that the relative phase in the lengthwise direction of the optical gain fiber falls within a predetermined range containing 0.5 Π.
|Method for adjusting electro-optic modulator in laser device, and laser device|
A laser device includes: a signal light source that outputs seed light; an electro-optic modulator that chops a portion of the seed light outputted from the signal light source and outputs signal light; an optical amplifier that amplifies the signal light outputted from the electro-optic modulator; a wavelength conversion optical element that wavelength converts the signal light amplified by the optical amplifier; a converted light detector that detects the signal light that has been wavelength converted by the wavelength conversion optical element; and an eu control unit that controls the operation of the electro-optic modulator, wherein the eu control unit is adapted, in the state in which the seed light is being outputted, to adjust bias voltage of the electro-optic modulator on the basis of the applied voltage when the intensity of the signal light after wavelength conversion detected by the converted light detector becomes substantially maximum.. .
|Modular, high energy, widely-tunable ultrafast fiber source|
A modular, compact and widely tunable laser system for the efficient generation of high peak and high average power ultrashort pulses. Peak power handling capability of fiber amplifiers is expanded by using optimized pulse shapes, as well as dispersively broadened pulses.
|Few mode rare earth doped optical fibers for optical amplifiers, and amplifiers using such fibers|
According to some embodiments a few moded optical fiber includes a glass core structured to provide light amplification at an amplification wavelength and a cladding surrounding the core. According to some embodiments the core of the few moded optical fiber includes a portion that has an average concentration of rare earth dopant which is lower by at least 30%, and preferably by at least 50%, than the average concentration of the rare earth dopant at another portion of the core that is situated further from the core center..
|Frequency agile high power microwave generator|
A multi-cycle digital high power microwave (mcd-hpm) source includes a microwave transmission line (mtl) to which a plurality electrically charged thin film transmission lines (tftl's) are connected by switches. The switches are activated in sequence to generate a square wave at a microwave output frequency.
|Polarization stabilization scheme for un-cooled self-tuning cavity for colorless ultra broadband pon|
An optical transmitter for a wdm (wavelength division multiplexing) passive optical network (pon) and a wdm pon comprising such an optical transmitter are disclosed. An optical transmitter comprises first mirror and second mirrors at first end and second ends of a cavity; an optical amplifier positioned within the cavity upstream from the first mirror and for amplifying light polarized in a first polarization plane; an optical waveguide for transmitting light from the optical amplifier to the second mirror and vice versa; a first non-reciprocal polarization rotator upstream of the optical amplifier and downstream of the optical waveguide; and a second non-reciprocal polarization rotator upstream of the optical waveguide and downstream of the first mirror; wherein the first and second non-reciprocal polarization rotators rotate the polarization of the light such that light which re-enters the optical amplifier after having been reflected by the second mirror is polarized in the first polarization plane..
|Optical amplifier and method|
An optical amplifier includes: a rare-earth doped fiber configured to amplify signal light to thereby produce a amplified signal light; a gain control circuit configured to control an optical gain of the rare-earth doped fiber; a photodetector configured to detect intensities of different wavelength of light obtained from the amplified signal light; and an abnormality detection circuit configured to detect an abnormality of the signal light in accordance with a ratio or a difference between the intensities of the different wavelength.. .
|Free space optical communications link node, network and method of transmitting traffic|
A free space optical communications link node 10 comprising transmitter apparatus 12 comprising a first optical transmitter 14, arranged to transmit high priority traffic on a first upstream optical signal having a first wavelength and at a first optical signal power, and a second optical transmitter 16 arranged to transmit low priority traffic on a second upstream optical signal having a second wavelength, different to the first wavelength, and at a second optical signal power. The node 10 further comprises receiver apparatus 18 comprising a first optical amplifier 20 arranged to receive and amplify a first downstream optical signal having a third wavelength and carrying high priority traffic and a second downstream optical signal having a fourth wavelength, different to the third wavelength, and carrying low priority traffic.
|Semiconductor optical amplifier device and optical matrix switch|
The semiconductor optical amplifier device includes a plurality of active units. Each active unit includes an active stripe structure of an optical amplifying medium and a current circuit configured to inject current into the corresponding active stripe structure.
|Hybrid optical amplifier with optimized noise figure|
Methods for optimizing a noise figure of a variable gain hybrid amplifier (ha) which includes a variable gain raman amplifier with adjustable average gain gr and gain tilt tr and a variable gain lumped amplifier with adjustable average gain gl and gain tilt tl. In various embodiments, the methods include receiving as input a required hybrid amplifier average gain gh value and a required gain tilt th value and deriving a set of gr, tr, gl and tl values which yield an optimal optimized hybrid amplifier nf and satisfy the conditions gr+gl=gh and that tr+tl is within a specified hybrid amplifier operating tilt range.
|Fiber optic network adjustment|
A number of fiber optic networks, nodes, and methods are disclosed. One fiber optic network embodiment includes a network module including a star coupler for receiving a signal from a number of nodes and outputting a combined signal, including the received signals, to the number of nodes, and the number of nodes optically connected to the network module, the number of nodes including a transmit module including a first adjustable optical amplifier and a number of optical emitters, a receive module including a second adjustable optical amplifier and a number of receivers, and a controller coupled to the transmit and receive modules for adjusting the first and second optical amplifiers in response to the combined signal..
|Tunable pumping light source for optical amplifiers|
A tunable external cavity laser for use as a pump laser in an optical amplifier such as a raman amplifier or erbium doped fibre amplifier comprising a semiconductor gain device (12) operable to provide light amplification, a diffraction grating (18) for selecting the wavelength of operation of the laser and a mems actuator for changing the selected wavelength. A plurality of gain devices can be coupled together to improve the bandwidth or gain of the optical amplifier..
|Optical network component and method for processing data in an optical network|
An optical network component is provided comprising a semiconductor optical amplifier with an input and an output, wherein the input is connected to a light source, wherein the output is connected to an amplitude modulator, wherein the semiconductor optical amplifier converts an amplitude modulated signal from the amplitude modulator to a phase modulated signal and provides the phase modulated signal at its output. Also, a transmitter comprising at least one such optical network component is suggested..
|High peak power optical amplifier|
A method and apparatus for providing a high peak power optical beam. The method includes interleaving pulse trains of different wavelengths and spatially and temporally overlapping the different wavelengths to produce an amplified output beam with very high peak power..
|Wavelength conversion laser system|
The present invention relates to a wavelength conversion laser system and provides a wavelength conversion laser system including a semiconductor optical amplifier, an optical condenser that condenses light emitted from the optical amplifier, a diffraction grating plate that induces wavelength components of the light having passed through the optical condenser in different directions, and an optical very large scale integration (vlsi) processor.. .
|Optical transmission apparatus and method|
An optical transmission apparatus includes a splitter configured to split an input optical signal into a first optical signal and a second optical signal, a signal length determiner configured to determine a signal length of the first optical signal per unit time, an optical power detector configured to detect an optical power of the first optical signal per unit time, a delay unit configured to delay the second optical signal, an optical amplifier configured to amplify the second optical signal delayed by the delay unit, a first excitation light source configured to generate an excitation light to be supplied to the optical amplifier, and a first excitation light power adjustor configured to adjust an optical power of the excitation light to be supplied to the optical amplifier in accordance with the signal length of the first optical signal and the optical power of the first optical signal.. .
|Method and apparatus for control of excess pump power in optical amplifiers|
A method for control of excess pump power in an optical amplifiers is disclosed. In one particular exemplary embodiment the method comprises a state model for the amplifier gain medium ground energy level inversion and a closed loop control tracking a desired degree of excess pump power..
|Optical amplifier and optical amplifier control method|
An optical amplifier includes: a temperature-adjustment-unit that is provided in a wavelength-fixing-unit that fixes a center-wavelength of an excitation-light-source, and adjusts a temperature of the wavelength-fixing-unit, which causes the center-wavelength of the excitation-light-source to vary; a temperature-measurement-unit that measures the temperature of the wavelength-fixing-unit and a temperature of a gain-equalization-unit that equalizes gains of the signal-light on which the raman amplification is performed using the excitation-light-source; a shift-amount-obtaining-unit that obtains a shift amount data of the center-wavelength of the excitation-light-source from a first-storage-unit and obtains a shift amount of the center-wavelength of the wavelength-band from a second-storage-unit; and a control unit that obtains a temperature-data of the-wavelength-fixing-unit, which corresponds to a difference between two shift amounts that are obtained by the shift amount obtaining unit, from the first-storage-unit, and controls the temperature of the wavelength-fixing-unit based on the obtained temperature-data.. .
|Ase swept source with self-tracking filter for oct medical imaging|
An integrated swept wavelength tunable optical source uses a narrowband filtered broadband signal with an optical amplifier and self-tracking filter. This source comprises a micro optical bench, a source for generating broadband light, a tunable fabry perot filter, installed on the bench, for spectrally filtering the broadband light from the broadband source to generate a narrowband tunable signal, an amplifier, installed on the bench, for amplifying the tunable signal.
|Co-modulation of dbr laser and integrated optical amplifier|
In an embodiment, a laser chip includes a laser, an optical amplifier, a first electrode, and a second electrode. The laser includes an active region.
|Optical amplifier and resonator|
An optical amplifier includes: a first optical fiber, through which seed light and excitation light propagate; an optical coupler that inputs the excitation light into the first optical fiber; a first lens to which the seed light and the excitation light output from the first optical fiber are input and which increases diameters of the seed light and the excitation light; a glass rod doped with rare earth elements to be excited by the excitation light, to which the seed light and the excitation light output from the first lens are input and which amplifies and outputs the seed light as output light; a second lens to which at least the output light output from the glass rod is input and which decreases a diameter of the output light; and a second optical fiber to which the output light output from the second lens is input.. .
|Monolithic integrated structure comprising a buried heterostructure semiconductor optical amplifier and a photodetector|
A monolithic integrated structure comprising a buried heterostructure semiconductor optical amplifier and a deep ridge optical receiver comprising such structure are disclosed.. .
|Optical receiver implemented with semiconductor optical amplifier in front end thereof and method to control the same|
An optical receiver implemented with a semiconductor amplifier (soa) whose temperature is controlled by the automatic temperature control (atc) circuit is disclosed. The optical receiver further includes an optical de-multiplexer, optical devices, a signal processor, and a controller.
|Banded semiconductor optical amplifier|
A semiconductor optical amplifier module may include a beam splitter to split an optical signal into two polarization optical signals including a first polarization optical signal with a transverse magnetic (tm) polarization provided along a first path of two paths, and a second polarization optical signal with a transverse electric (te) polarization provided along a second path of the two paths; a first rotator to rotate the tm polarization of the first polarization optical signal to te polarization; a first semiconductor optical amplifier to amplify the rotated first polarization optical signal to output a first resultant optical signal; a second semiconductor optical amplifier to amplify the second polarization optical signal; and a second rotator to rotate the polarization of the amplified second polarization optical signal to output a second resultant optical signal; and a beam combiner to combine the first resultant optical signal and the second resultant optical signal.. .
|Apparatus and method for stabilizing wavelength tunable laser|
An apparatus and method for stabilizing an output of a laser is provided. An optical amplifier oscillates light having a first wavelength band.
|Pulsed laser sources|
Modelocked fiber laser resonators may be coupled with optical amplifiers. An isolator optionally may separate the resonator from the amplifier.
|Multi-mode optoelectronic oscillator|
A multi-mode optoelectronic oscillator (mm-oeo) includes an oeo cavity having an input for receiving an rf signal and an rf output. The oeo cavity includes a) a first laser having a first laser output, a second laser having a second laser output, b) a modulator having i) a first input coupled to the first laser output, ii) a second input coupled to the second laser output, iii) a third input, iv) a first modulator output ,and v) a second modulator output, c) a semiconductor optical amplifier (soa) having an input coupled to the first modulator output and having an soa amplified output, d) a photodetector coupled to the soa amplified output and having an output, and e) a coupler having an input coupled to the photodetector output and having a first output coupled to the third modulator input and a second output, whereby an amplified rf signal is produced at the oeo rf output..
|Method to control optical receiver implemented with semiconductor optical amplifier and method to control optical communication|
A method to control an optical receiver implemented with a semiconductor optical amplifier (soa) is disclosed. The soa has a p-n junction operable in a pd mode when it is supplied with a zero or reverse bias.
|Tunable laser module|
The present disclosure relates to a tunable laser module including a light gain area unit for outputting an optical signal; an optical distributor for separating the optical signal output from the light gain area unit; two comb reflection units for reflecting a part of optical signals separated by the optical distributor and allow a part of the optical signals to penetrate; two phase units for changing phases of the optical signals penetrating the two comb reflection units; an optical coupler for combining the optical signals of which the phases are changed by the two phase units; and an optical amplifier for amplifying the optical signal combined by the optical coupler, wherein the light gain area unit oscillates a laser by totally reflecting the optical signals reflected by the two comb reflection units.. .
|Suppression of parasitic optical feedback in pulse laser systems|
A pulsed laser system includes a variable attenuator located in a secondary optical path bounded by a target surface and one or more reflective surfaces outside of the primary laser oscillator of the laser system. The variable attenuator isolates an output optical amplifier of the laser system from light reflected from the target during time periods between laser pulses.
|Optical coupling structure and array optical amplification module|
An optical coupling structure includes an optical amplifier array configured to include a plurality of optical amplifiers arranged in an array direction, an optical fiber array configured to include a plurality of optical fibers arranged in the array direction, and an optical coupling system that optically couples the optical amplifier array and the optical fiber array, wherein, in a non-array direction orthogonal to the array direction, the optical coupling system optically couples beams of light signals to an end face of the optical amplifier array in parallel with a waveguide direction of the optical amplifiers, and optically couples the beams to an end face of the optical fiber array obliquely to the end face of the optical fiber array in the non-array direction.. .
|Light source and recording apparatus|
There is provided a light source including a mode-lock laser unit that includes a semiconductor laser and an external resonator unit and emits a laser beam having a predetermined frequency, the semiconductor laser including a saturable absorber unit that applies a reverse bias voltage and a gain unit that applies a gain current, a semiconductor optical amplifier that performs amplification modulation on the laser beam emitted from the mode-lock laser unit, a laser clock generating unit that generates a laser clock synchronized with the laser beam based on a signal detected from the saturable absorber unit when the laser beam oscillates in the mode-lock laser unit, and a modulating unit that generates a driving current synchronized with the laser clock and applies the driving current to the semiconductor optical amplifier.. .
|Optical amplifier and optical transmission system|
An optical amplifying apparatus that amplifies an optical signal, including an input section whereto the optical signal is inputted, a laser light source that generates laser light, the laser light source including an uncooled semiconductor laser device, an optical fiber that amplifies the optical signal by a stimulated emission based on the laser light from the laser light source, an output section that outputs the optical signal amplified by the optical fiber, and a passive optical component disposed between the optical fiber and the output section. The laser light source is thermally coupled to the optical fiber and/or the passive optical component via a thermally conductive medium.
|Optical amplifier arrangement|
The invention relates to an optical amplifier arrangement for amplifying ultra-short pulsed laser radiation comprising a mode-locked laser (1) and two or more optical amplifiers (3) arranged downstream of the laser (1) in the propagation direction of the laser radiation. Optical amplifier arrangements of this type are known in the prior art.
|Optical brillouin sensing systems|
According to one embodiment, an optical sensing system may include a gated optical amplifier, one or more triggering devices, and an optical coupler. The gated optical amplifier can receive a pulse signal and transform the pulse signal into an amplified pulse signal having an amplified peak portion.
|Excitation light distribution device, excitation light distribution method, optical amplification system and node device|
For the purpose of reducing the cost and power consumption of an optical amplification system provided with an optical amplifier, an excitation light distribution device of the present invention comprises an excitation light source output unit which outputs excitation light, an optical branching unit with variable branching ratio which branches and outputs the excitation light, and a control unit which, on the basis of information on an optical signal to be amplified by the excitation light outputted by the optical branching unit, controls at least either the branching ratio of the optical branching unit or the optical output power of the excitation light source output unit.. .
|Optical receiving device|
An optical receiving device includes: an optical amplifier configured to amplify a wavelength multiplexed optical signal; a demultiplexer configured to demultiplex the amplified wavelength multiplexed signal into optical signals of a plurality of wavelengths; optical receivers configured to regenerate the demultiplexed optical signals; error correction units configured to correct a bit error in the regenerated optical signals; and main control unit. The control unit adjusts rxdtv of the optical receiver for receiving optical signals of a given wavelength to the optimal value in the state where the gain of the optical amplifier is lowered from that of a normal operation such that the occurrence of bit errors in the optical signals of the other wavelengths does not exceed the correction capability of the error correction unit..
|Organic/inorganic hybrid optical amplifier with wavelength conversion|
A device and related fabrication method is provided for an organic/inorganic hybrid optical amplifier with a function of converting infrared light to visible light. The hybrid device integrates an inorganic heterojunction phototransistor (hpt), an embedded metal electrode mirror with a dual function as an optical mirror and charge injection electrode, and an organic light emitting diode (oled).
|Filtered ase swept source for oct medical imaging|
An integrated swept wavelength optical source uses a filtered ase signal with an optical amplifier and tracking filter. This source comprises a micro optical bench, a source for generating broadband light, a first tunable fabry perot filter, installed on the bench, for spectrally filtering the broadband light from the broadband source to generate a narrowband tunable signal, an amplifier, installed on the bench, for amplifying the tunable signal, and a second tunable fabry perot filter, installed on the bench, for spectrally filtering the amplified tunable signal from the amplifier.
|Energy-efficient optical source|
An optical source includes a set of n light sources that provide a corresponding set of n optical signals having n carrier wavelengths. These optical signals are combined into a seed optical signal and transported to a substrate using an optical fiber.
|Optical amplifier and manufacturing method of optical amplifier|
An optical amplifier includes multiple semiconductor optical amplifiers (soas) provided on a semiconductor substrate and having different wavelength bands to be amplified; multiple branching paths that branch an input optical signal and input the branched optical signals into the parallel soas, respectively; and multiple combining paths that combine and output the optical signals after amplification by the soas.. .
A sensor arrangement for monitoring a oil reservoir comprises a sensor array (1) comprising a plurality of sensor units (5) located over an area to be monitored; an interrogator unit (30) comprising a transmitter (402) for transmitting optical signals and receiver for obtaining data on the reservoir from the sensor units, a demodulator (418) for demodulating the received signals, and a recorder (420) for recording the demodulated signals. The arrangement includes an uplink optical cable (408) for transmitting the signals to the sensor array and a downlink optical cable (410) for transmitting signals from the array to the receiver.