155 results about "Large array" patented technology

The invention relates to an aliasing image intelligent deformation small target identification algorithm based on detector multiplexing, and relates to the technical field of aliasing image target identification, and the algorithm comprises the steps: designing a detector multiplexing optical system; designing a view field coding element, and splicing the whole system; simulating and generating a motion track of the early warning target under the space-based background; the target motion trail is imaged through a detector multiplexing optical system; aliasing video simulation of moving target imaging is carried out; an intelligent deformation small target recognition algorithm is applied to the aliasing image, and a moving target is recognized; target resolution and field-of-view positioning are realized by using the relevance between the inter-frame track of the moving target and the light spot shape. According to the aliasing image intelligent deformation small target recognition algorithm based on detector multiplexing, light originally imaged on a large-area-array detector is folded and imaged on a small-area-array detector, and therefore the purpose that the small-area-array detector receives large-view-field imaging is achieved.

The embodiment of the invention provides an antenna array, a radar, electronic equipment and a vehicle, and belongs to the technical field of antennas. Wherein the antenna array comprises a transmitting antenna array and a receiving antenna array. The transmitting antenna array and the receiving antenna array are used for forming a virtual array. The transmitting antenna array comprises at least two transmitting sub-arrays which are arranged at intervals in the first direction, and the distance between every two adjacent transmitting sub-arrays in the first direction is smaller than or equal to the aperture length of the receiving antenna array in the second direction. The receiving antenna array comprises at least two receiving sub-arrays arranged along the second direction, and each receiving sub-array comprises at least two receiving antennas arranged at intervals along the second direction. And the receiving antenna array satisfies the relational expression: 0 < dn-dn-1 < = 0.5 lambda. The antenna array provided by the embodiment of the invention has the characteristics of large array aperture, high resolution, no grating lobe and low side lobe.

A number of MOSFET architectures provide high-voltage capability (both drain-source breakdown voltage BVDSS and ON-state breakdown voltage BVON), low current leakage, and extended linearity. Embodiments of the invention overcome the limitations of conventional NEDMOS and LDMOS device designs by providing a low-resistance path for hole collection and by purposefully exhibiting multiple voltage thresholds VTH in different segments of the device. Embodiments includes NEDMOS and LDMOS device designs having multiple body contact regions for improved hole collection, sub-gate doped stripes or segments for even better hole collection and linearity, and sub-gate doped edge regions for increased local VTH and thus decreased current leakage. P– hole-collection stripes and P+ body contact regions may be formed of a semiconductor material that includes germanium. The inventive MOSFETs may be arranged as multi-MOSFET array elements, and multiple array elements may be arranged in a larger array.

This disclosure relates to a wideband extremely large array antenna system and an OFDM-based hybrid beamforming for hybrid-field interference control of the same. The wideband extremely large array antenna system for OFDM-based hybrid beamforming of this disclosure may include a transmitter having a plurality of transmit antennas, and a receiver capable of communication with the transmitter and having a plurality of receiving antennas, and the system may be configured to perform a first step for designing a common analog beamforming matrix for all subcarriers between the transmitter and the receiver, and a second step for designing a baseband beamforming matrix for each of the subcarriers.

The invention discloses a super-resolution communication perception integration method and system based on sparse MIMO, and belongs to the field of wireless communication and signal processing. Signals emitted by all users are received through a sparse array, and signal processing is carried out to estimate the two-dimensional angle of arrival of the users; pairing the two-dimensional angles by using a permutation matrix; a beam forming matrix is constructed by matching the estimated angle, and channel gain is estimated by using a small amount of pilot frequency, so that super-resolution two-dimensional sensing and efficient channel estimation of users in the system are realized. According to the method, the characteristic of large array aperture of the sparse array is combined, the problem of low positioning precision of dense distribution of multiple users is solved under the condition of not increasing hardware loss, a large amount of pilot frequency resources are saved, and the channel estimation precision is further improved.

A number of MOSFET architectures provide high-voltage capability (both drain-source breakdown voltage BVDSS and ON-state breakdown voltage BVON), low current leakage, and extended linearity. Embodiments of the invention overcome the limitations of conventional NEDMOS and LDMOS device designs by providing a low-resistance path for hole collection and by purposefully exhibiting multiple voltage thresholds VTH in different segments of the device. Embodiments includes NEDMOS and LDMOS device designs having multiple body contact regions for improved hole collection, sub-gate doped stripes or segments for even better hole collection and linearity, and sub-gate doped edge regions for increased local VTH and thus decreased current leakage. P− hole-collection stripes and P+ body contact regions may be formed of a semiconductor material that includes germanium. The inventive MOSFETs may be arranged as multi-MOSFET array elements, and multiple array elements may be arranged in a larger array.

The invention discloses a reflective all-dielectric polarization beam-combining grating suitable for any wave band. The reflective all-dielectric polarization beam-combining grating is composed of a grating etching layer, a phase matching layer, a periodic film system and a grating substrate in sequence from top to bottom. The invention has the characteristics of easy preparation, wide band and high diffraction efficiency, can effectively solve the problems of low PBS anti-laser damage threshold and low synthesis efficiency in the current polarization beam combination technology, and provides solid component support for the realization of the larger array scale and higher power laser synthesis technology in the future.

The invention provides a beam forming optimization method for an ISAC system based on a reconfigurable antenna structure, and the method comprises the steps: firstly, designing an energy-saving DFBS based on a TTD reconfigurable antenna architecture based on a downlink terahertz large-scale MIMO ISAC system; the DFBS is switched between the modular MIMO and the uniform MIMO by dynamically controlling the antenna sub-arrays; in the sensing stage, modular MIMO is deployed, and a larger array aperture is realized by using fewer antennas; the beam dispersion effect at the main lobe and the grating lobe is utilized to realize rapid user perception; in the communication stage, uniform MIMO is adopted, and a TTD network is activated to reduce the near-field beam dispersion effect; then, based on the channel state information obtained in the sensing stage, proposing a joint optimization problem of analog / digital hybrid beam forming and TTD network delay so as to maximize a system sum rate; finally, analog beam forming and time delay are designed through a serial time delayer method, and then alternating iteration optimization solution is carried out on digital beam forming.

The invention discloses a near-field CSI distributed estimation method for broadband XL-MIMO, and the method comprises the steps: firstly, enabling a center LPU to estimate a path time delay parameter of a center sub-array channel, enabling other LPUs to rapidly extrapolate the path time delay parameters of other sub-array channels, and transmitting an estimation result to a CPU; then, based on near-field wave beam squint and parameter symmetry characteristics brought by a large array and a large bandwidth, the CPU fuses time delay parameters estimated by different sub-arrays, and decouples and independently estimates near-field channel parameters including angle, distance and range parameters; then, the CPU transmits the estimated near-field channel parameters back to the LPUs, and each LPU independently estimates the path gain of the sub-array channel; and finally, transmitting the estimated path gain to a CPU (Central Processing Unit) by the LPUs, and further reconstructing a full-dimensional broadband near-field channel. The problems that the CSI acquisition calculation complexity is too high and the reconstruction precision is low in a large-array and large-bandwidth scene are solved.

The invention relates to the technical field of chip packaging, in particular to a super-large array multi-chip packaging structure, a multi-chip packaging process and a detection method thereof, the packaging structure is used for packaging a plurality of chips on a tube shell, the packaging structure comprises a placing groove formed in the tube shell, the plurality of chips are arranged in the placing groove, and the chip packaging process is used for packaging the plurality of chips on the tube shell. A surface bonding pad used for being electrically connected with the chip is further arranged in the containing groove. Through the distribution mode of combining the tube shell with the bonding pads on the front surface and the back surface, the electrical connection of the chip can be effectively improved, and the connection mode not only ensures that the distance between transition leads on the upper surface and the lower surface is shortest, reduces signal noise and prevents signal distortion, but also facilitates wiring and welding of a flexible board; the problem of chip buckling deformation can be effectively reduced through a step-by-step packaging process, and the mounting position precision of the chip and the lens can be ensured to be within a required range through position precision detection, so that the precision of the chip and the lens during packaging is realized.

An in-memory computing (IMC) accelerator using a high-density operation circuit and a low-power sense amplifier as a peripheral circuit includes a plurality of dynamic random-access memory (DRAM) banks each including a pair of cell arrays, a data supply logic, a memory, and a controller for IMC, a global SRAM, and a top-level controller, wherein the cell array includes a plurality of subarrays, each of the subarrays includes a DRAM array including a big array and a little array, and an arithmetic circuit configured to perform an operation, and the arithmetic circuit includes a sense amplifier configured to amplify a bit line voltage difference, and a compact multiply-accumulate (MAC)-single instruction multiple data (SIMD) unit (CMSU) for an MAC operation and an SIMD operation, so that functionality of an in-memory operation is diversified.

The liquid nitrogen testing Dewar comprises a cold end cold head, a variable-temperature cold head, a variable-temperature rotating block, a transition block, a loading cold head, the large-area-array detector, an optical window, a liquid nitrogen storage cavity and a shell. The cold energy of the liquid nitrogen storage cavity forms a solid conduction path through the cold-end cold head, the variable-temperature cold head and the loading cold head, and the variable-temperature cold head and the loading cold head adopt a low-heat-conduction hollow structure to construct a basic temperature difference; the variable-temperature rotating block is connected with the variable-temperature cold head and the transition block in a threaded fit mode, and the cooling capacity obtaining degree of the object carrying cold head is changed by means of position adjustment. According to the invention, flexible and accurate temperature control within the range of 80K-180K can be realized, the cooling capacity transmission is efficient, the use is convenient, and the device is suitable for testing and screening of large-area-array detectors with different temperature requirements.

The invention provides an avalanche photodiode with asymmetric optical resonance and a photosensitive array, and the avalanche photodiode comprises an electrode layer which is internally provided with a first windowing region; the top reflecting mirror is arranged in the first windowing area, the transmittance of the incident side of the top reflecting mirror to the light with the target wavelength is higher than a preset transmittance threshold value, and the reflectivity of the emergent side of the top reflecting mirror to the light with the target wavelength is higher than a preset reflectivity threshold value; the substrate is arranged on the emergent side of the top reflecting mirror; the buffer layer is arranged on one side, deviating from the top reflecting mirror, of the substrate; the active region is arranged on the side, away from the top reflector, of the buffer layer; and a bottom high reflective metal film. The top reflector and the bottom high-reflectivity metal film form an asymmetric optical resonant structure, and the purposes of filtering and absorption enhancement are achieved. And the bottom high-reflection metal film is low in process difficulty and suitable for preparation of large-array devices.

The invention provides an ultra-large array plane radar satellite decoupling vacuum thermal test method, which comprises the following steps of: arranging a satellite and radar antennas in a vacuum tank, detaching the radar antennas from the satellite, arranging the radar antennas on one side of the satellite side by side, and respectively arranging infrared simulation devices around the satellite to simulate external thermal flow; a wave absorbing device is arranged on an antenna array plane to absorb microwaves and simulate external heat flow, the power level of an infrared simulation device is adjusted according to the heat radiation level of the satellite surface, the power level of the wave absorbing device is adjusted according to the microwave emission power and the heat radiation level of the antenna array plane, and a vacuum thermal test is performed on the satellite and the antenna. According to the invention, vacuum thermal tests on a satellite and a radar antenna due to an overlarge antenna array plane can be avoided, a whole-satellite microwave wireless emission state test can be carried out, extremely high-risk operation caused by hanging and unfolding in an antenna tank is avoided after the antenna and the satellite are decoupled, the tank occupation period of links such as test state establishment and withdrawal is greatly shortened, and the test efficiency is improved. And the model development efficiency is improved.

The invention relates to the technical field of avalanche detectors, particularly provides an avalanche detector and a preparation method, and aims to solve the problem that small-size pixels are difficult to obtain in the preparation process of an existing avalanche detector. In order to achieve the purpose, the preparation method of the avalanche detector comprises the steps that a groove is formed in an epitaxial layer through a shallow groove isolation technology, the side, away from a substrate, of the epitaxial layer is isolated into islands arranged in an array mode, and then doping is conducted on the bottom and the side wall of the groove to form a protection ring surrounding the islands; and finally, forming a gain layer and a contact layer in the island to form a pixel. Good isolation between pixels can be obtained by adopting a shallow trench isolation technology, so that the avalanche detector with small size and large array pixels is obtained.

The invention provides a target object angle estimation method using a large-scale array antenna to carry out high angle analysis, which receives an input signal matrix through the array antenna, the input signal matrix is an emission signal or a reflection signal of at least one target object, and the method comprises the following steps: S1, inputting the input signal matrix to a first operation model, obtaining the number of target objects and roughly estimated target angles corresponding to the positions of the target objects; s2, inputting the number of the target objects and the input signal matrix into a second operation model for singular value decomposition, and obtaining a noise matrix; s3, obtaining an iteration angle range through the roughly estimated target angle obtained in the step S1; and S4, inputting the complex tracking matrix and the noise matrix corresponding to the iteration angle range into a third operation model, and performing iteration of the angle range, thereby obtaining a precise target angle.

A miniaturized, automated method for controlled printing of large arrays of nano- to femtoliter droplets by actively transporting mother droplets over hydrophilic-in-hydrophobic (“HIH”) micropatches. The technology uses single or double-plate devices where mother droplets can be actuated and HIH micropatches on one or both plates of the device where the droplets are printed. Due to the selective wettability of the hydrophilic micropatches in a hydrophobic matrix, large nano- to femtoliter droplet arrays are created when mother droplets are transported over the arrays. The parent droplets are moved by various droplet actuation principles. Also, a method using two plates placed one top another while being separated by a spacer. One plate is dedicated to confirming and guiding parent droplets by using hydrophilic patches in a hydrophobic matrix, while the other plate contains HIH arrays for printing of the droplets. When the parent droplet guidance plate is rotated over the plate dedicated to printing of nano- to femtoliter droplets, the droplets are dispensed inside the HIH array utilizing their selective wettability. The methods allow the parent droplets to move over the HIH arrays many times, providing advantages for performing bio-assays or miniaturized materials synthesis in nano- to femtoliter sized droplets. With controlled evaporation of the dispensed droplets of solution, large arrays of printed material can be generated in seconds. The methods provide a nano- to femtoliter droplet printing technique for a wide variety of applications, e.g., protein- or cell-based bio-assays or printing of crystalline structures, suspensions of nanoparticles or microelectronic components.

This invention discloses a level shifting structure for an ultra-large area array ultra-low temperature infrared image sensor, comprising a conversion signal input transistor; a level clamping transistor whose gate receives a level VREF, and whose source is connected to the source of a feedback transistor, the gate of an inverting N-transistor, and the gate of an inverting P-transistor; the drain of the level clamping transistor connected to the source of the conversion signal input transistor; the drain of the conversion signal input transistor grounded; the gate of the conversion signal input transistor connected to IP; the drain of the feedback transistor connected to the source of a pull-up transistor, whose gate is connected to IP, and whose drain is connected to power supply VDD; the source of the inverting P-transistor connected to power supply VDD, whose drain is connected to the source of the inverting N-transistor, and whose drain is grounded; and a level VREF generated by a level VREF clamping matching voltage generation circuit. This ensures that the source-drain voltage of the conversion signal input transistor (low threshold transistor) does not exceed 1.2V, ensuring that the device operates within its normal voltage range and avoiding the risk of breakdown.

A method for sharing reconfigurable array modes in a MIMO frequency-modulated millimeter-wave radar array is proposed. Based on the echo signal data matrices obtained after analog-to-digital conversion of different modes, range-dimensional Fast Fourier Transform (FFT) and velocity-dimensional FFT are performed on them respectively to obtain the range-Doppler spectrum of different transmit / receive antenna combinations. Different modes with the same gain in the MIMO radar system are combined. Among the combinations with the same gain, the mode corresponding to the largest virtual array aperture in the horizontal and elevation directions under that gain is selected. The angles of these two modes are resolved and matched separately, and then combined to achieve the maximum virtual array aperture resolution. Digital beamforming is used to match the angle information obtained under the maximum aperture virtual array in the horizontal and elevation dimensions. This invention can effectively increase the maximum array aperture in the original modes with the same gain by utilizing the complementary effect between different reconfigurable array modes while using virtual array reconfigurable technology or MIMO technology.

The application relates to a fast demodulation system and method for a large-scale microcavity array on a chip, and the system comprises a frequency-sweeping laser, a first fiber coupler, a microcavity array transmission signal arm, an auxiliary interference reference arm, a same-frequency trigger arm and a signal processing device. The first fiber coupler is used for dividing a light source into a first light source and a second light source. The microcavity array transmission signal arm is used for receiving the first light source of the frequency-sweeping laser, and the first light source enters a large-array microcavity sensor device after polarization processing, and is converted into an electric signal after receiving the disturbance of an external sensing signal. The auxiliary interference reference arm is used for receiving the second light source of the frequency-sweeping laser, and two beams of coherent light with opposite phases are obtained after processing the second light source, and then the coherent light is converted into an electric signal. The same-frequency trigger arm is used for transmitting a same-frequency trigger signal emitted by the frequency-sweeping laser. The signal processing device is used for signal acquisition and processing. The application effectively suppresses the frequency-axis distortion and spectral line broadening caused by the frequency-sweeping nonlinearity of the laser, and can be applied to the accurate demodulation of a large-scale, high-Q microcavity sensing array.

The application discloses a method for obtaining and separating a scattering field of a large-scale array antenna, and the steps are as follows: obtaining a radiation field of each unit array of a subarray, and calculating a scattering field of an antenna mode item in each unit array; using the scattering field of the antenna mode item in each unit calculated by a pattern multiplication method to solve a mutual coupling correction matrix; using the mutual coupling correction matrix to correct the scattering field of the structure mode item calculated by the pattern multiplication method; adding the scattering field of the antenna mode item and the scattering field of the structure mode item to obtain a scattering field of the array; equivalently constructing the subarray and performing phase compensation to obtain a scattering field of each unit of the large-scale array antenna; and obtaining a total scattering field of the large-scale array antenna and the scattering field of the total antenna mode item and the total structure mode item through field superposition. The application introduces the mutual coupling correction matrix and the subarray theory, avoids directly performing matrix operation on the large-scale array antenna, improves the calculation speed, and solves the problem that a large amount of calculation time and resources are consumed when a scattering field of the large-scale array antenna is obtained in the prior art.

The invention discloses a region decomposition-based two-dimensional array resistivity inversion method, electronic equipment, a storage medium and a device. The method comprises the steps that area decomposition is conducted on a large array lateral logging response data set based on the layer interface position of a target area, a plurality of sub-areas are obtained, and every three adjacent stratums form one sub-area; the thickness and the center point position of each stratum are calculated, and then the thickness and the center point position of each sub-region are obtained; constructing a one-dimensional inversion model based on the stratum to perform one-dimensional array resistivity inversion; and constructing a two-dimensional inversion model based on the sub-regions to perform two-dimensional array resistivity inversion, and taking a one-dimensional inversion result as an initial parameter value of the two-dimensional inversion model. The method fully considers the influence of radial mud invasion and longitudinal surrounding rock layers, and strengthens the information constraint of the upper and lower well sections, thereby weakening the influence of surrounding rock, guaranteeing the extraction precision of the real resistivity of the stratum, and achieving the rapid and accurate imaging of the two-dimensional profile of the resistivity of the stratum.

The utility model discloses a surface array optical fiber collimator, is constituted by mould pressing lens array, a plurality of pigtail, a plurality of connecting pipe or ridge hole plate, one side of lens array is array convex surface, the other side is a plurality of ridge inclined plane, one side end surface of connecting pipe or ridge hole plate and lens array gluing, the other side end surface and pigtail gluing, since every optical fiber collimator is through the precise light adjustment between pigtail relative to plano-convex lens, and is fixed after the axial transition through connecting pipe or ridge hole plate, can guarantee the mechanical positioning accuracy index of every collimator and the optical performance index in the whole surface array optical fiber collimator, and the quality can be guaranteed, in addition, the utility model has compact structure and low material cost, and easy to assemble, the yield is high, is suitable for building large array.

A conformal array beamforming method based on the maximum SNR criterion comprises the following steps: (1) establishing a global coordinate system model for the conformal cylindrical array; (2) establishing a local coordinate system for each array element using Euler coordinate transformation; (3) calculating the element amplitude gain of each element based on the signal incident angle under the local coordinates and the element radiation pattern; (4) calculating the element activation threshold condition and determining whether the element is activated based on the element activation gain; (5) achieving the maximum SNR array output based on the element activation determination result. This invention can achieve the maximum SNR output of a conformal array of a certain size with incident signals at any angle, and the algorithm is simple. This invention can be applied to fields such as communication and radar.

The invention discloses a satellite infrared multi-probe metadata homogenization method based on variational self-encoding, which comprises the following steps of: acquiring multichannel observation brightness temperature data of a satellite large-array infrared detector, constructing a variational self-encoder model, designing a comprehensive loss function, adopting a dynamic weight scheduling mechanism, gradually adjusting the weight of each loss item in a training process, and carrying out uniformization on the multi-channel observation brightness temperature data of the satellite large-array infrared detector. And carrying out iterative training by adopting Adam and a piecewise learning rate, storing an optimal model, reconstructing observation data by utilizing the trained model, and outputting homogenized multi-detection-element hyperspectral brightness temperature data. The method can automatically extract and learn the complex nonlinear characteristics of the hyperspectral data, has higher accuracy and robustness compared with an empirical correction method, and improves the consistency and stability of the data of the large-array detector; and the method has relatively high expandability and universality.

The invention discloses a memory low-voltage write circuit and method for high-bandwidth magnetic computing and a memory device. The memory low-voltage write-in circuit for high-bandwidth magnetic computing comprises a plurality of memory arrays, a source line multiplexing unit and inter-array buffer stage units, wherein the inter-array buffer stage units are arranged between two adjacent memory arrays; the storage array generates a write-in voltage within a preset low threshold range according to the control signal; the source line multiplexing unit multiplexes the source lines of the two adjacent storage arrays and the write-in driving unit; and the inter-array buffer stage unit generates and outputs a control signal of the next-stage storage array according to the bit line driving signal and the source line driving signal of the previous-stage storage array. Data writing is completed directly through logic voltage, the area overhead of a level converter in a traditional writing circuit is saved, and the problem of insufficient driving caused by parasitism in a large array is solved through the design of the buffer stages between the arrays.

The invention relates to the technical field of sensing product testing, in particular to a super-large array packaging conductivity testing device which comprises a wafer testing table, an open circuit testing plate and a short circuit testing plate, an objective table is installed at the top of the wafer testing table, and a swing arm positioning seat is installed at the top of the wafer testing table and on the back face of the objective table. The outer wall of the swing arm positioning seat is provided with a test probe, the top of the wafer test bench and the back surface of the swing arm positioning seat are provided with a main control unit, and the outer wall of the main control unit is connected with the swing arm positioning seat through a test line. According to the super-large array packaging conductivity testing device, the open circuit testing plate and the short circuit testing plate in the device are used for testing the to-be-tested product, and the problems that an existing testing device and an existing testing method cannot directly point-contact the two ends for measurement, the accuracy of a testing result is poor, the efficiency is low, and the product is prone to being damaged are solved.

The application relates to the technical field of data storage, in particular to an array data storage method, an electronic device and a medium, which comprises the following steps: S1, initializing an array A and recording corresponding default values D in the array A, wherein the total number N of elements in the array A is greater than a preset first threshold value, and the expected total number M of non-default value elements in the array A is less than a preset second threshold value; S2, initializing an empty tree structure T; S3, obtaining an array subscript of a non-default value to be newly added in the array A and a corresponding value; S4, storing the array subscript of the non-default value to be newly added as a key and the corresponding value as a value in a to-be-newly-added node corresponding to the tree structure T, inserting the to-be-newly-added node into the tree structure T according to subscript sequence, and updating the tree structure T; and S5, if all elements in the array A are processed, ending the process, or returning to step S3. The application improves the memory utilization rate of large array data storage.

The utility model discloses an array electro-acupuncture structure, an excitation circuit and medical beauty equipment, relates to the technical field of medical equipment, and discloses the array electro-acupuncture structure comprising a plurality of electro-acupuncture units; each electric needle unit is of a matrix structure composed of a plurality of electric needles, the plurality of electric needles of each electric needle unit are electrically connected, and each of rows and columns of each electric needle unit at least comprises two electric needles; each electro-acupuncture unit is used for sequentially receiving current excitation output energy; the electroacupuncture units are adjacently spliced to form the array electroacupuncture structure, and the array electroacupuncture structure is a matrix structure. A large array electro-acupuncture structure is divided into small electro-acupuncture unit matrixes for excitation, and the electro-acupuncture number of each electro-acupuncture unit is limited to ensure certain area dispersed current. The electric needles in each electric needle unit are electrically connected so as to receive unified current excitation and output energy. Due to the fact that the number of the electric needles excited at the same time is reduced, the difference between the electric needles is reduced, and therefore energy distribution can be more uniform through sequential excitation of the electric needle units.