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24results about How to "Improve Noise Performance" patented technology

Multi-stage broadband low-noise amplifier with variable gain

A variable-gain multistage broadband low-noise amplifier comprises N (N > = 2) stages of amplifying circuits, the first stage of amplifying circuit and the second stage of amplifying circuit are connected through a first inter-stage matching circuit, a main circuit switch and an inter-stage matching circuit are sequentially connected between the subsequent stages of amplifying circuits in series, the input end is connected with an input matching circuit in series to be connected to the first stage of amplifying circuit, and the second stage of amplifying circuit is connected with a second stage of amplifying circuit. The Nth-stage amplification circuit is connected in series with a main switch and an output matching circuit in sequence to a signal output end; from the second stage, each stage of amplifying circuit and the main switch are integrally connected with a bypass switch in parallel; a source degeneration inductance scheme is adopted for input matching, and the noise performance is optimized; the overall gain flatness is improved through inter-stage matching; a multi-stage LC structure is adopted for output matching, and broadband matching in different gain modes is achieved; according to the invention, control of each switch is realized through logic level signals, switching of multiple gain modes is realized, the designed bandwidth reaches more than 10GHz, and the overall gain flatness and the noise coefficient in different gain modes are kept consistent.
Owner:XIDIAN UNIV +1

Noise reduction structure applied to DC motors

ActiveCN224459504UImprove Noise Performancereduce diffuseSound sourcesAcoustic noise reduction
This utility model relates to a noise reduction structure for a DC motor, wherein the noise reduction structure (1) is disposed within a cavity for accommodating a commutator (2) and close to the sound source. The noise reduction structure (1) can be a honeycomb structure, a square structure, a circular structure, or a regular polygonal structure, and can be disposed on the bottom surface of the cavity, or simultaneously on the sidewalls and bottom surface of the cavity. The noise reduction structures (1) can be evenly distributed on the bottom surface and sidewalls of the cavity, or staggered. In addition, the noise reduction structure (1) can also be disposed within the cavity of a gearbox (5), including at the bottom of the gearbox cavity (6), or simultaneously on the bottom and cavity walls of the gearbox cavity (6). Using this noise reduction structure for a DC motor, the sound waves generated by the sound source are effectively reflected and canceled out by the noise reduction structure, thus reducing the noise of the DC motor and possessing certain practical value.
Owner:INTEVA PROD ZHENJIANG

Low-noise amplification chip, low-noise amplifier and radio frequency front-end module

The invention provides a low-noise amplification chip, which comprises a chip, a first power supply port arranged on the chip, a control module, a low-noise amplification module and a first voltage stabilization unit, and is characterized in that the control module comprises an interface unit and a decoding unit; the first power supply port is connected to the power supply end of the interface unit and the power supply end of the decoding unit, the signal input end of the interface unit is configured to receive clock signals and data signals, and the signal output end of the interface unit is connected with the signal input end of the decoding unit. The decoding unit comprises a plurality of signal output ends, the plurality of signal output ends of the decoding unit are connected to the plurality of control ends in the low-noise amplification module, and the first voltage stabilizing unit is connected to a connection path between the first power supply port and the power supply end of the decoding unit; therefore, jittering of the control signal finally output to the low-noise amplification module by the decoding unit is avoided, and the noise performance of the low-noise amplification chip is improved.
Owner:RADROCK (SHENZHEN) TECH CO LTD

22-74GHz low noise amplifier chip applied to 5G NR

The invention discloses a 22-74GHz low noise amplifier chip applied to 5G NR, which comprises four modules, namely an input matching network, a broadband input amplification stage, a broadband output amplification stage and an output matching network, the four modules are connected in sequence, and a signal enters from the input end of the input matching network and is output from the output end of the output matching network. A shunt feedback technology is introduced into the circuit, and low-frequency bandwidth expansion is enhanced by adding a feedback resistor and a capacitor; a double-induction peak value technology is introduced, and inductors are added to a base electrode and a collector electrode of a transistor, so that gain is increased, and noise performance is improved; a resonant feedback compensation equalization technology is introduced, and a resonant feedback inductor and a capacitor are added to compensate high-frequency gain, so that the bandwidth is further expanded. According to the technology, the complexity of the circuit is reduced, the bandwidth is expanded, the chip area is reduced, and great practical significance is achieved.
Owner:TIANJIN UNIV

Electronic device comprising touch sensor integrated display

An electronic device may include a display panel that displays an image through pixels and a window located above the display panel and through which light emitted from the display panel is transmitted. The display panel may include a light emitting area including the plurality of pixels; a plurality of organic light emitting elements located in the light emitting area to form the plurality of pixels; a thin film encapsulation layer covering the plurality of organic light emitting elements; a plurality of color filters arranged to overlap with the plurality of organic light emitting elements; and a plurality of light blocking portions located between the color filters to block the light. A plurality of first touch electrodes disposed between the plurality of light blocking portions and the thin film encapsulation layer and a plurality of second touch electrodes disposed between the thin film encapsulation layer and the window may be included.
Owner:SAMSUNG ELECTRONICS CO LTD

SUV tire with good noise performance

ActiveCN222473812UImprove Noise Performancereduce noiseTyre tread bands/patternsStructural engineeringSport utility vehicle
The utility model discloses an SUV (sports utility vehicle) tire with good noise performance, which relates to the technical field of special tires for SUVs and comprises a central land part, an outer auxiliary land part, an inner auxiliary land part, an outer side land part, an inner side land part, a circumferential main groove and a circumferential auxiliary groove, the central land part, the outer side auxiliary side land part, the inner side auxiliary side land part, the outer side edge side land part and the inner side edge side land part are arranged in the circumferential direction, the inner side edge side land part extends on the outer surface of the tread in the circumferential direction, the central land part is located between the two circumferential main grooves in the surface of the tire, and the two circumferential auxiliary grooves are located on the outer sides of the two circumferential main grooves. The outer side auxiliary side land parts and the inner side auxiliary side land parts are located between the circumferential main grooves and the circumferential auxiliary grooves adjacent to each other on the surface of the tire, the outer side edge land parts and the inner side edge land parts are located on the outer sides of the circumferential auxiliary grooves, various pitches, most-purpose design and optimized arrangement pitches are achieved, and the noise performance of the tire pattern running on the road surface is improved.
Owner:SHANDONG LINGLONG TIRE CO LTD

Low-mismatch charge pump and clock data recovery circuit suitable for current mode logic

The invention provides a low-mismatch charge pump suitable for current mode logic and a clock data recovery circuit, relates to the technical field of low-mismatch charge pumps, and aims to improve the matching precision and the overall performance of charge and discharge currents of the charge pump. Comprising a first level shift module, a second level shift module, a P tube differential pair, an N tube differential pair, a first operational amplifier circuit, a second operational amplifier circuit, a current matching branch and a voltage bias module, the second operational amplifier circuit is connected to a current matching branch, the current matching branch is connected to an N tube differential pair through a tenth field effect transistor, the current matching branch is connected to a P tube differential pair through a ninth field effect transistor, and the N tube differential pair and the P tube differential pair are connected through the first operational amplifier circuit; and the first level shift module and the second level shift module are respectively connected to the P tube differential pair and the N tube differential pair. The charge pump has the advantage of effectively reducing current mismatch when charge and discharge currents of the charge pump exist at the same time.
Owner:CHENGDU CORPRO TECH CO LTD

System and method for improving signal-to-noise ratio of signal assisted by optical domain

The invention discloses an optical domain assisted signal to noise ratio improving system and method, and belongs to the technical field of microwave photons and radars. The system comprises a first optical signal, a slave laser and an optical fiber, and the first optical signal serves as an input signal and is injected into the slave laser through the optical fiber; the slave laser is used for receiving a first optical signal and outputting a second optical signal after nonlinear photon resonance amplification, the slave laser works in a light injection locking state, and in the light injection locking state, the difference between the wavelength of free oscillation of the slave laser and the wavelength of the first optical signal meets a preset range; and the output optical power from the laser and the optical power of the first optical signal are in a weak injection proportional relationship. Differential amplification of signals and noise is achieved through a simple framework, the noise is suppressed while the signals are amplified, and the microwave link noise performance is improved from a new dimension.
Owner:AEROSPACE INFORMATION RES INST CAS

tire

ActiveCN113442655BImprove Noise PerformanceTyre tread bands/patternsGroove widthTransverse groove
The tire of the present invention maintains off-road performance and improves noise performance. The tire (1) is provided with shoulder longitudinal grooves (3), crown longitudinal grooves (4) and middle transverse grooves (5). The middle transverse grooves (5) include an outer portion (10) and an inner portion (11) inclined in the same direction as the first inclined portion (6) of the shoulder longitudinal grooves (3), and an intermediate portion (12) inclined in the opposite direction to the outer portion (10) and the inner portion (11). The outer portion (10) is smoothly continuous with the first inclined portion (6). The groove width WA1 of the outer portion (10) at the outer end position (10e) is greater than the groove width WA2 of the outer portion (10) at the inner end position (10i), and the groove width WB1 of the inner portion (11) at the outer end position (11e) is greater than the groove width WB2 of the inner portion (11) at the inner end position (11i).
Owner:SUMITOMO RUBBER INDUSTRIES LTD

Shock absorption and noise reduction device of electronic parking device

The utility model discloses a shock absorption and noise reduction device of an electronic parking device, which is characterized by comprising an electronic gear set, a vibration isolation gasket and brake calipers, the vibration isolation gasket is mounted on the electronic gear set; the brake calipers are installed on the electronic gear set, and the vibration isolation gasket is located between the electronic gear set and the brake calipers to separate the electronic gear set from the brake calipers. According to the device, the speed of manufacturing and installing a vibration isolation gasket sample piece is high, and a noise reduction scheme can be quickly verified and optimized; the verification efficiency can be greatly improved compared with that of manufacturing an MGU manual sample piece; the method can be used on mass-produced parts, and the noise performance of products of our company is improved.
Owner:WANXIANG QIANCHAO SHANGHAI AUTOMOTIVE SYST

Voltage-controlled oscillator and electronic device

ActiveCN114567261Breduce in quantityReduce the number of stacked layersOscillations generatorsHigh level techniques
The application discloses a voltage-controlled oscillator and electronic equipment, comprising bias circuit, core circuit and buffer stage circuit connected in sequence, wherein the core circuit comprises PMOS cross-coupled pair, NMOS cross-coupled pair and LC resonant loop connected in parallel. Compared with the prior voltage-controlled oscillator, the core circuit of the voltage-controlled oscillator utilizes PMOS cross-coupled pair and NMOS cross-coupled pair to provide negative resistance, reduces the number and stack number of active devices in the core circuit, and is beneficial to optimization of noise performance of the voltage-controlled oscillator and low-voltage implementation. Meanwhile, the voltage-controlled oscillator adjusts the substrate voltage of the PMOS cross-coupled pair and the NMOS cross-coupled pair in the core circuit through the bias circuit, so that the voltage-controlled oscillator can work at low voltage and low power consumption, the current of the core circuit and the amplitude of the MOS tube transconductance changing with environmental factors such as temperature can be reduced, and the circuit robustness is improved.
Owner:ZHONGKE SAIFEI (GUANGZHOU) SEMICON CO LTD

A capacitor feedback low noise amplifier circuit

The invention discloses a capacitor feedback low noise amplifier circuit, comprising an operational amplifier, an input capacitor C in , feedback capacitor C f , common mode signal feedback resistor R fp , NMOS tube M f , switch SW 1 and switch SW 2 . And the signals related to the capacitor feedback low noise amplifier circuit disclosed by the present invention include, input signal V in , output signal V out , common mode signal V CM , subthreshold voltage signal V Sub‑TH , MOS tube turn-on voltage signal V ON . The capacitor feedback low noise amplifier circuit proposed in the present invention adopts capacitors for signal feedback, thereby overcoming the defect of deterioration of thermal noise performance of the inverting amplifier circuit caused by the feedback path formed by resistors in the traditional inverting amplifier circuit. At the same time, the inverting amplifier circuit has the ability to obtain DC common mode signals while maintaining low noise performance. The present invention can be applied to medical, audio, sensitive signal capture and other scenarios to improve the noise performance of the low noise amplifier circuit and reduce the design cost of the low noise amplifier circuit.
Owner:SHIHEZI UNIVERSITY

Tire with concave-convex grooves in tread pattern groove wall

The invention relates to the technical field of tread pattern design, and discloses a tire with concave-convex grooves in tread pattern groove walls, which comprises a tread, four circumferential grooves formed in the tread and extending along the tire circumference C direction, and transverse grooves extending towards the outer side of the tire width L direction. The circumferential grooves and the transverse grooves divide the tread into a plurality of block-shaped patterns, and the block-shaped patterns sequentially comprise an inner side shoulder block, an inner side close-to-center block, a middle block, an outer side close-to-center block and an outer side shoulder block from the inner side to the outer side of the tire. According to the tire with the concave-convex grooves in the tread pattern groove wall, the transverse groove of the tread is optimally designed, the groove wall of the groove is specially designed, and design parameters such as the position and the size of the concave-convex grooves in the groove wall are reasonably configured, so that the effects that the noise, the control safety performance and the durability can reach relatively high levels, and other performances are kept optimal are achieved.
Owner:GITI RADIAL TIRE (ANHUI) CO LTD

Low-noise rubber tire

ActiveCN222451860Uimprove noiseImprove Noise PerformanceTyre tread bands/patternsSound waveClosed cavity
The utility model relates to the technical field of tires, and discloses a low-noise rubber tire which comprises a hub, a first acoustic isolation pad is mounted on the surface of the hub, an inner tube is mounted on the surface of the first acoustic isolation pad, and a second acoustic isolation pad is mounted on the outer side of the inner tube. According to the utility model, the first acoustic isolation pad and the second acoustic isolation pad are arranged, and the first acoustic isolation pad is made of the rubber composite material, so that when a vehicle runs, a closed cavity is formed in the tire, and the first acoustic isolation pad absorbs vibration and sound wave energy generated by resonance of the cavity and prevents the vibration and sound wave energy from being transmitted to a vehicle structure and a surrounding environment; the second acoustic isolation pad is made of polyurethane materials and has excellent sound absorption and vibration reduction performance, when a vehicle runs, the second acoustic isolation pad can effectively absorb vibration and sound wave energy, additional loads of the vehicle cannot be increased due to the light weight characteristic of the second acoustic isolation pad, and the noise generated by the tire is reduced.
Owner:QINGDAO WANGYU RUBBER

A low-noise large full-well TDI-CMOS image sensor readout circuit

The invention relates to a low-noise large full-well TDI-CMOS image sensor readout circuit, which belongs to the field of CMOS image sensors; the circuit comprises a buried-channel CCD structure and a readout module; the buried-channel CCD structure comprises a p-type substrate, an n-type buried channel, four CCD electrodes and a transmission gate TG; the n-type buried channel is arranged on the upper surface of the p-type substrate; the four CCD electrodes are evenly distributed on the upper surface of the n-type buried channel; the transmission gate TG is arranged on the upper surface of the n-type buried channel and is located on the outside of the four CCD electrodes; a groove is arranged on the upper surface of the n-type buried channel; the readout module comprises an FD node and an analog readout front-stage circuit; the FD node is connected to the analog readout front-stage circuit; the FD node extends into the groove to realize the connection between the readout module and the n-type buried channel; the invention is suitable for a CCD-CMOS fusion type TDI image sensor, and in particular can improve the noise performance of the sensor under the premise of high buried channel depletion potential, high charge transfer efficiency and large full-well buried channel CCD pixel design.
Owner:BEIJING RES INST OF SPATIAL MECHANICAL & ELECTRICAL TECH

Car window sunshade curtain system for improving wind noise performance of car and car

The invention belongs to the technical field of automobiles, and discloses an automobile window sunshade curtain system and an automobile capable of improving the automobile wind noise performance, the automobile window sunshade curtain system comprises a sunshade curtain and automobile window glass, and a sound absorption structure stretching out and drawing back in the normal direction of a glass surface is arranged between the sunshade curtain and the automobile window glass; the projection shape of the sound absorption structure in the plane parallel to the glass face corresponds to the projection shape of the vehicle window glass in the plane parallel to the glass face. By detecting the running speed of the vehicle and the opening and closing state of the vehicle window glass, the sunshade curtain is driven to be completely opened, and the sound absorption structure is unfolded, so that a sound insulation structure is formed between the vehicle window glass and the sunshade curtain.
Owner:DONGFENG MOTOR GRP

Biplanar DC-RF compound field driving coil system for optical pump magnetometer

According to the biplane DC-RF compound field driving coil system for the optical pump magnetometer, the complexity, noise and volume of the system are reduced and the measurement sensitivity and integration degree are improved by unifying the geometric configuration and differential parameters of the biplane, and particularly, the high-frequency magnetic field distortion and frequency dispersion effect in a magnetic shielding environment are optimized. Specifically, the problems of insufficient magnetic field uniformity, enhanced electromagnetic interference and RF magnetic field distortion in a large-volume area caused by non-uniform coil configuration in the traditional design are solved, so that the high uniformity of the magnetic field is realized, and the space utilization rate and the signal quality of a system are improved, and the system is characterized by comprising a standard coil unit and a radio frequency coil unit, the standard coil unit and the radio frequency coil unit both adopt a biplanar coil configuration after simulation optimization, the biplanar coil comprises a left planar coil and a right planar coil, and the left planar coil and the right planar coil are parallel, coaxially and symmetrically arranged on the two sides of a target area and used for generating and compensating a shimming magnetic field.
Owner:BEIHANG UNIV

Self-vibration mixer with adjustable broadband

The invention discloses a broadband-adjustable natural vibration mixer, and relates to the technical field of radio frequency microwave mixing. Comprising a double-gate FET (Field Effect Transistor) which provides a local oscillation signal under the action of direct current bias and a YIG (Yttrium Indium Gallium) thin-film resonator and mixes the local oscillation signal with a radio-frequency signal, a direct current bias network which provides a direct current power supply for the double-gate FET, a source feedback network which is connected with a source of the double-gate FET, and a source feedback network which is connected with a source of the YIG thin-film resonator. And the YIG thin film resonator, the radio frequency input, filtering and matching network and the intermediate frequency output, filtering and matching network are connected with a grid electrode of the direct current bias network connected with the double-grid FET transistor. The YIG thin-film resonators are adopted to achieve the broadband adjustment range of multiple octaves and the excellent phase noise characteristic, the double-gate field effect transistors are adopted to achieve higher linear frequency conversion gain and better noise performance, meanwhile, the inherent isolation between the two gates reaches 20 dB or above, and the noise performance is improved. Good isolation between a local oscillator signal and a radio frequency signal can be realized.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Noise reduction keyboard

The utility model provides a noise reduction keyboard which comprises a keyboard key base and a key cap movably arranged on the top of the keyboard key base, a key cap shaft is fixedly installed at the center of the bottom of the key cap through a screw, and the bottom end of the key cap shaft penetrates through and extends into the keyboard key base. A positioning cylinder is fixedly mounted at the center of the top of the keyboard key base through a bolt, the keycap shaft movably penetrates through the center of the positioning cylinder, a positioning plate is fixedly mounted at the top end of the interior of the positioning cylinder on the keycap shaft through a screw, and a first spring is fixedly mounted at the center of one side of the bottom of the positioning plate through a bolt. The further buffering effect is achieved through the supporting plate and the second spring below the key cap shaft, the sound attenuation effect of the key cap in the keyboard key base is good, then the key cap enters the buffering base through the arc-shaped base block, the buffering and noise reduction effect is improved through the third spring below the buffering base, the structure is stable, noise is eliminated by reducing the noise layer by layer, and the service life of the key cap is prolonged. The buffering effect is stable and simple, and good noise reduction is achieved.
Owner:SHENZHEN NEWUNITE ELECTRONIC CO LTD

An isolated detection system and vehicle

The application provides an isolated detection system and a vehicle. The isolated detection system comprises a power supply circuit, a signal input circuit, an isolation circuit and a signal processing circuit. The power supply circuit is configured to output a first low-voltage power supply. The signal input circuit is connected to a positive electrode of a high-voltage DC bus, a negative electrode of the high-voltage DC bus and the power supply circuit. The isolation circuit is connected to the signal input circuit and the power supply circuit. The signal processing circuit is connected to the isolation circuit and configured to determine the voltage of the high-voltage DC bus based on the output current of the isolation circuit. The system can directly convert the high-voltage power supply of the high-voltage DC bus into a low-voltage power supply and output the low-voltage power supply to the high-voltage side circuit through the power supply circuit, so that the high-voltage side circuit can work normally, the power supply cost is low, the high-voltage side power supply and the low-voltage side power supply are isolated from each other, the power supply stability is high, the use reliability of each device in the system is improved, and the detection and operation reliability of the system are improved.
Owner:GREAT WALL MOTOR CO LTD

A high-gain operational amplifier circuit for a sigma-delta adc

PendingCN122600916AHigh precision requirementsGuaranteed output voltage swing
The application claims a high-gain operational amplifier circuit for Sigma-Delta ADC. The circuit comprises a main operational amplifier, a gain-improving auxiliary operational amplifier, a bias circuit and a switched-capacitor common-mode negative feedback circuit. The main operational amplifier serves as the main body of the circuit, has a high gain and a wide bandwidth; the auxiliary operational amplifier improves the output impedance and effectively improves the DC gain of the operational amplifier; the bias circuit is used to provide appropriate DC bias voltage for the main operational amplifier and the auxiliary operational amplifier; the switched-capacitor common-mode negative feedback is used to stabilize the output common-mode voltage. The application uses the auxiliary operational amplifier to improve the gain, ensures a high input-output swing of the operational amplifier, improves the DC gain of the operational amplifier, adopts a symmetrical switched-capacitor common-mode negative feedback, ensures the bandwidth range and reduces the nonlinearity of the circuit.
Owner:NANJING MODULUS ZHIXIN MICROELECTRONICS TECH CO LTD

Tire

PendingCN119567763AEnsure handling stabilityImprove Noise PerformanceTyre tread bands/patternsControl theoryMechanical engineering
The invention provides a tire capable of maintaining steering stability and improving noise performance. A tire is provided with a tread portion (2). The first land portion (7) is provided with a plurality of first lateral grooves (11), and the second land portion (8) is provided with a plurality of second lateral grooves (12). The plurality of first lateral grooves (11) are arranged in a first layout throughout the circumference of the tire. In the first layout, the first lateral grooves (11) are arranged such that the first pitch (P1) of the first lateral grooves (11) becomes a type number a, and in the paired first lateral grooves (11), the first ends (11a) are provided at the same position in the tire circumferential direction as the second ends (11b). The plurality of second lateral grooves (12) are arranged in a second layout. In the second layout, the second lateral grooves (12) are arranged so that the second pitch (P2) of the second lateral grooves (12) becomes the number b of types, and the number b of types of the second pitch (P2) is greater than the number a of types of the first pitch (P1).
Owner:SUMITOMO RUBBER INDUSTRIES LTD

Optical fiber image transmitting element with square structure and preparation method of optical fiber image transmitting element

The invention relates to an optical fiber image transmitting element with a square structure and a preparation method thereof, and the preparation method comprises the following steps: drawing a square wire: matching a square skin glass tube with a square core glass rod with a high refractive index, and then carrying out monofilament drawing to obtain a drawn square monofilament; drawing the square core material glass rod with high refractive index into a square gap wire; the method comprises the following steps: preparing a square light absorption material glass rod from light absorption material glass, and drawing the square light absorption material glass rod into a square light absorption wire; drawing a square primary multifilament, and drawing a square secondary multifilament; and finally, carrying out hot melt pressing molding and processing molding to obtain the optical fiber image transmitting element with a square structure. The optical fiber image transmitting element with the square structure can be applied to an enhanced charge-coupled device, and has the advantages of high coupling efficiency, high resolution, high contrast ratio, high light transmittance and clear imaging.
Owner:CHINA BUILDING MATERIALS ACADEMY CO LTD

Hybrid power supply circuit

The application discloses a hybrid power supply circuit and relates to the technical field of transformers. The circuit comprises a primary circuit and a secondary circuit arranged on one side of the primary circuit. The primary circuit comprises a first primary coil and a second primary coil for electrically coupling a voltage source respectively. The first primary coil and the second primary coil are subjected to common mode filtering and / or differential mode filtering by adjusting the phase. The secondary circuit comprises a first secondary coil and a second secondary coil for electrically coupling a load respectively. The position of the first secondary coil corresponds to the first primary coil, and the position of the second secondary coil corresponds to the second primary coil. The first secondary coil and the second secondary coil generate induced electromotive forces with the first primary coil and the second primary coil respectively. The hybrid power supply circuit can simultaneously have the functions of noise suppression and energy conversion.
Owner:DONGGUAN LIANBAO PHOTOVOLTAIC TECH CO LTD