153results about How to "Low signal loss" patented technology

The invention discloses an enhanced radiation three-dimensional packaging structure and a packaging method for the same. The enhanced radiation three-dimensional packaging structure comprises a multilayer substrate, devices and an interconnection circuit for connecting the devices on the substrate, a micro-channel, a radiation plate, an external radiation device and a water pump. According to the enhanced radiation three-dimensional packaging structure and the packaging method for the same, a micro-fluid convection heat transfer mode is used for quickly conducting away the vast majority of heat produced by heating devices, and the three-dimensional interconnection circuit consisting of good metal conductors connected with the heating devices in the substrate is used for assisting the conduction of the heat into and out of the substrate in a metal heat conduction way; the radiation plate at the bottom of the substrate can be connected with various types of external radiation devices, so that the problem of thermally-induced failures of a multi-chip electronic product is effectively solved; process conditions are easy to implement, and the enhanced radiation three-dimensional packaging structure and the packaging method for the same are low in cost and convenient to machine in batches, and can be widely applied to a plurality of fields of aerospace, information communication, biochemistry, medicines, automatic control, consumer electronics and the like related to national electronic development and national security.

A class of modular, double-sided, edge-mounted printed circuit (PC) board modules and an associated modular network architecture for constructing stripline signal processing networks including high-power analog amplifiers and beam forming networks for driving multi-beam antenna systems. The stripline signal processing networks are characterized by network elements constructed from defined-length segments of transmission media configured to exhibit precisely determined phase and impedance characteristics. These circuits may also include conventional passive “lumped” electrical elements, such as resistors, capacitors and inductors; non-linear circuit elements such as diodes; and active electrical elements, such as amplifiers and transistors.

The embodiment of the invention discloses a WiFi transmission power value regulation method. The WiFi transmission power value regulation method comprises the following steps: acquiring signal transmission rates in transmitting data to WiFi hot spots; according to the preset mapping relationship between the signal transmission rates and WiFi transmission power values, acquiring an assembly of the WiFi transmission power values corresponding to the signal transmission rates; detecting signal quality parameters in transmitting data to the WiFi hot spots; selecting the minimal WiFi transmission power value in the assembly, which enables the signal quality parameters are larger than a threshold value, and according to the minimal WiFi transmission power value, transmitting data to the WiFi hot spot. The invention also discloses a WiFi transmission power value regulation device. By the adoption of the WiFi transmission power value regulation method and device, the power consumption of a terminal can be reduced.

The invention discloses electronic equipment integrated with a millimeter wave array antenna. The millimeter wave antenna comprises a millimeter wave antenna array, a main printed circuit board (PCB),a battery and a first metal middle frame, the method is characterized in that the first metal middle frame comprises a metal frame positioned on the appearance surface of the electronic equipment anda large-area metal block for supporting and grounding; the metal frames comprise a metal frame I, a metal frame II, a metal frame III and a metal frame IV; a first double-sided groove area is arranged in the metal frame I, grooves are formed in the front surface and the back surface of the first double-sided groove area, a metal partition is arranged in the middle of the first double-sided groovearea, the first groove area is used for arranging a millimeter wave antenna array, and the millimeter wave antenna array consists of more than two antenna units and is arranged in an array form. According to the invention, the optimal radiation direction of the millimeter wave array antenna can be realized, performance degradation caused by shielding of the millimeter wave array antenna by surrounding devices or the environment when consumers use the millimeter wave array antenna is avoided, the feeding and grounding realization mode is simple, and the realization cost is low.

The invention discloses a micro phase delay quantity light delay line array switch, on the same horizontal light path, in turn placing first single optical fiber polarization beam splitting collimator, first polarization rotating switch, first polarization distributor, first delay compensation plate, first polarization combiner, second polarization rotating switch, second polarization distributor, second polarization combiner, and second single optical fiber polarization beam splitting collimator, where the first micro reflector is placed on the vertical light path of the first polarization distributor, the second micro reflector is placed on the vertical light path of the first polarization combiner; the third micro reflector is placed on the vertical light path of the second polarization distributor, and the fourth micro reflector is placed on the vertical light path of the second polarization combiner; the second delay compensation plate is placed between the third and fourth micro reflectors and they together form the same horizontal light path. And it can implement 0-0.6ns delay, suitable to micro light delay control and regulation; and has advantages of small device bulk and low signal loss.

The invention relates to the technical field of machinery, and discloses a laser radar multipoint distance measurement system on the basis of diffraction optical components. The laser radar multipoint distance measurement system comprises a laser signal transmitting device, a laser signal receiving device and a signal processing system. The signal processing system is connected with the laser signal transmitting device and the laser signal receiving device, the laser signal transmitting device comprises a pulse laser device, and a collimation system, a beam expansion system, a diffraction grating and a half-transmitting and half-reflecting mirror are sequentially arranged in a light emitting direction of the pulse laser device; the light emitting direction of the pulse laser device is positioned in a transmitting direction of the half-transmitting and half-reflecting mirror, and the laser signal receiving device is arranged in a reflecting direction of the half-transmitting and half-reflecting mirror. The laser radar multipoint distance measurement system has the advantages that laser light transmitted by the pulse laser device can be divided into a plurality of light beams at equal angles or unequal angles by the diffraction grating, and the light beams can be transmitted via the half-transmitting and half-reflecting mirror, then face media at to-be-measured distances, can be reflected by the media at the to-be-measured distances and then can be reflected to the laser signal receiving device by the half-transmitting and half-reflecting mirror.

The invention discloses a zero-tolerance depth-controllable drilling method for a circuit board. The drilling method comprises a depth-controllable drilling process and a laser drilling process; in the depth-controllable drilling process, the drilling depth is 0-0.1 mm away from a target layer; and, in the laser drilling process, a medium layer on the surface of the target layer is removed, so that a zero-tolerance drilled hole is obtained. Because the mechanical depth-controllable drilling precision is 0.05 mm, the drilling depth is set to 0.05-0.1 mm away from the target layer when mechanical depth-controllable drilling is carried out; the problem that the distance between the mechanical drilling bottom and a next circuit layer is too small due to too-deep mechanical drilling or the next circuit layer of the target layer is drilled can be avoided; then, on the basis of mechanical depth-controllable drilling, laser drilling is carried out; after the medium layer on the surface of the target layer is removed; the hole depth achieves the target layer rightly; therefore, zero-tolerance depth-controllable drilling is realized; signal loss of micro-wave and radio-frequency products can be effectively reduced; the quality and the reliability of the circuit board are ensured; and requirements of clients on high-order products can be satisfied.

The invention provides a single-mode optical fiber bidirectional optical transceiver, which comprises a light emitting module, a light receiving module, a spot-size conversion structure and a wavelength division multiplexing module which is manufactured based on a silicon nitride technology, wherein the light emitting module is connected with an uplink optical signal transmitting end of the wavelength division multiplexing module, a downlink optical signal receiving end of the wavelength division multiplexing module is coupled and connected with the light receiving module by means of the spot-size conversion structure, an optical fiber connecting end of the wavelength division multiplexing module is connected with an optical line terminal by means of an optical fiber, the light receiving module, the wavelength division multiplexing module and the spot-size conversion structure are integrated on a same silicon substrate by adopting a silicon photonic technology, and the light emitting module is compounded and integrated on the silicon substrate. The single-mode optical fiber bidirectional optical transceiver can realize effective coupling between the wavelength division multiplexing module and the light receiving module, the light emitting module and the optical fiber, is uniform in waveguide size, can effectively reduce signal loss and reduce false reflection, and is insensitive to the ambient temperature.

The invention discloses an integrated laminated transformer based on two layers of metal, consisting of a substrate, a plurality of layers of mediums, a secondary coil and a primary coil, wherein the mediums are arranged on the substrate, and the secondary coil and the primary coil are arranged in the mediums; an upper plane of the first layer of medium, sequentially in the plurality of layers of mediums from the bottom up, is provided with two mutually isolated turns of secondary coil connected in parallel around the axial center, and one sides of parallel connection parts of the two turns of secondary coil are provided with opening grooves; an upper plane of the second layer of medium is provided with six mutually isolated turns of primary coil connected in series around the axial center; each two joint leading-out lines of the secondary coil and the primary coil are arranged side by side to separate off and lead out the opening grooves on one side of the secondary coil, wherein the each two joint leading-out lines are arranged in the same layer with the secondary coil, and the two joint leading-out lines of the primary coil are arranged between the two joint leading-out lines of the secondary coil. The integrated laminated transformer based on two layers of metal, disclosed by the invention, has the advantages of few occupied layers of metal, saved cost, high magnetic induction coefficient, strong coupling degree of signals, large bandwidth and wide application.

The embodiment of the invention provides a bow-tie cell artificial surface plasmon polariton transmission line integrated by a self-packaging substrate. The transmission line includes a first dielectric plate, a second dielectric plate, a third dielectric plate, a fourth dielectric plate and a fifth dielectric plate, wherein the second dielectric plate is provided with a first blind groove; the third dielectric plate is provided with a third blind groove; a metal layer of the first dielectric plate, a metal layer of the second dielectric plate, a grounding plate on the upper surface of the third dielectric plate, a metal layer on the lower surface of the third dielectric plate, a metal layer of the fourth dielectric plate and a metal layer of the fifth dielectric plate are all wire grounding ends, And each wire grounding end is connected through a metal through hole penetrating through the first dielectric plate, the second dielectric plate, the third dielectric plate, the fourth dielectric plate and the fifth dielectric plate. By adopting the technical scheme of the embodiment of the invention, through an electromagnetic shielding space formed by the first blind groove, the thirdblind groove and the metal through hole, the signal loss in the signal transmission process is reduced, and signals radiated outwards in the signal transmission process are reduced.

The invention discloses a multi-fiber connector and a method for fixing the aramid fibers of the fibers connected thereto. The fixing method comprises the following steps: arranging more than one winding pinion in a shell of the fiber connector for winding the aramid fibers of the fibers; grouping the fibers connected to the fiber connector and weaving the stripped off aramid fibers of each fiber of the group of fibers into a strand; and tightly winding the strands of woven aramid fibers on near-by winding pinions. The fixing mode of the invention avoids the limitation of thickness of rubber bricks on the length of the fibers in the conventional adhesion mode, allows the fibers to run around the near-by pinions freely without being limited, and can effectively reduce the length of the shell and the curvature of the fibers and signal loss caused by the curvature, increase the tensile-resistance stress points and the mechanical performance of the aramid fibers by winding the aramid fibers on the winding pinions, simplify operation process and avoid pollution during encapsulation.

There is provided a communication system and method using a part of human body (30)as an antenna in a body area network, and more particularly, to a communications system and method enabling wireless communications using a low frequency band without the use of a bulky antenna in such a manner that a transmitting-side communications device (10) applies electrical signals (1) to a human body via a transmitting-side coupler to allow a part of human body to act as an antenna, and electrical signals, occurring in another part of human body (3) due to radio frequency (RF) signals, are transferred to a receiving-side communications device via a receiving-side coupler (20).

The invention provides a method of achieving the switching of the standard peripheral component interconnect extended (PCIE) bus and a device. The method comprises the steps that the branch circuits of PCIE bus of the PCIE devices in need of switching and connections are determined; by the branch circuits determined utilizing the breakover of capacitors, the PCIE devices in need of switching and connections are connected. By the method of achieving the switching of PCIE bus and the circuit, the breakover of the branch circuits of the PCIE devices is achieved by capacitors, the signal loss of the PCIE bus is reduced.

The present invention relates to the radio frequency test technology field, especially to a method and a device of signal connection of a mainboard and a small board. The device comprises a radio frequency test device, and a mainboard and a small board arranged on the radio frequency test device. The main board is provided with a test bench, and the small board is provided with a radio frequency connection head; the test bench is configured to calibrate and test the indexes of radio-frequency signals; the radio frequency connection head is configured to connect the radio-frequency signals to a mobile phone antenna; and a radio-frequency connecting line is connected between the test bench and the radio frequency connection head. The method and device of signal connection of the mainboard and the small board are firm and stable in structure, small in occupied wiring area of the mainboard, low in cost and small in the radio-frequency signal insertion loss, etc.

The present invention relates to a phase shifter comprising a DGS and a radio communication module comprising the same. The phase shifter comprises: a first substrate; a microstrip formed on the firstsubstrate so as to extend in a first direction; a ground layer disposed with a space on the upper surface of the microstrip and having a defected ground structure (DGS) with a defected pattern formedtherein; a second substrate disposed on the ground layer; and a liquid crystal layer disposed in a space between the first substrate and the second substrate, wherein DC voltage is applied between the ground layer and the microstrip.

The invention discloses an ultra-short baseline positioning method based on an adaptive unscented Kalman filter. The ultra-short baseline positioning method based on the adaptive unscented Kalman filter comprises the following steps: step 1, an ultra-short baseline is used for underwater positioning; step 2, the position information of a mother ship and the position information of an underwater robot positioned by using the ultra-short baseline are sent to the underwater robot through a photoelectric hybrid cable; step 3, the underwater robot receives the position information sent by the mother ship; and step 4, the underwater robot fuses the position information with the carried accelerometer, inertial navigation, depth gauge and other sensors, and attenuates the noise according to the adaptive unscented Kalman filter. The ultra-short baseline positioning method based on the adaptive unscented Kalman filter has simple operation, and can improve the underwater positioning accuracy of the underwater robot by fusing the multiple sensors and the ultra-short baseline positioning information.

Disclosed is a coaxial cable male connector for transmitting super-high frequency signals, which is used in a coaxial cable connector for transmitting super-high frequency signals and is received in aconnector socket mounted on a printed circuit board (PCB) to connect multiple coaxial cables to the PCB. The coaxial cable male connector includes: a single or multiple coaxial cables each includingan inner conductor, an outer conductor, a dielectric, and a sheath, wherein the outer conductor, the dielectric, and the sheath are partially stripped to expose the inner conductor over a predetermined length, and a terminal of the exposed inner conductor is brought into electrical connect with a signal line terminal pad formed on the PCB; and a shielding can receiving the exposed inner conductorsof the single or multiple coaxial cables, securing and protecting ends of the exposed inner conductors, and blocking electromagnetic waves generated from the inner conductors.

The invention relates to the field of optical communication and the field of underwater acoustics, in particular to a cross-medium air-to-underwater laser-induced acoustic communication method and device. The time interval and energy of laser pulses emitted by a laser are controlled through digital information coding, thereby exciting laser signals with different frequencies and different characteristics; pulse laser signals are transmitted through air, so that laser energy interacts with a water medium in an optical breakdown mode after reaching the water surface, then laser pulses are converted into sound wave signals, the sound wave signals are spread in all directions underwater, and the sound wave signals are received through a hydrophone at any position underwater. Therefore, signal transmission from air to underwater is realized, information transmission is further carried out, and underwater acoustic communication is realized.

The invention discloses a multi-channel DDS (Direct Digital Synthesizer) chip substrate packaging structure and method, which are used for designing wiring of multi-channel differential pair signals,layout of a power supply ground plane and arrangement of bonding fingers and leading-out ends. The differential pair of each channel adopts an arc-shaped routing and non-parallel routing mode; power supply ground planes are laid in the horizontal direction, the lower layer and the lower layer of the differential pair, the power supply ground planes of all the channels are independent of one another and keep a certain isolation distance, crosstalk and coupling between the power supply ground planes of all the channels are reduced, signal loss of the multi-channel DDS chip is remarkably reduced,and isolation between all transmission channels is improved. The technical problems that in the prior art, attenuation of multi-channel DDS chip signals is increasingly serious, and the isolation degree between transmission channels is increasingly low are solved.

The invention provides a method and device for forming an optical waveguide in air by an ultra-short pulsed intense laser. To be specific, the method comprises: a beam shaping device and a focusing lens are arranged at an output terminal of an ultra-short pulse laser along an axis direction; a laser beam passing through the beam shaping device forms a laser beam with a hollow conical shape and thelaser beam is transmitted independently, wherein the cross section intensity is in circular-ring distribution; and when the laser beam passes the focusing lens, an annular light spot is formed at thefocusing plane and an annular symmetric filament is generated based on a non-linear effect. When the filament is formed, air ionization is caused by the intense laser and thus plasma is generated; and the plasma is a heat source and the air density of the ionized region is low and thus the refractive index is low. Comparatively speaking, the air density inside the cylinder as a non-ionization region is high and thus the refractive index is high, so that a cylindrical symmetric optical waveguide structure is formed. Because the thermal conductivity of air is low and the time needed by thermalbalancing is at an ms order or longer, an optical waveguide with the millisecond service life is formed. Besides, the optical waveguide can be used for transmitting laser beams with different modes bycontrolling a circular ring distribution parameter of the pulse laser.

The invention discloses a transmission system and method for transmitting wide frequency band simulating radio frequency signals through optical transmission media. The transmission system comprises an antenna, indoor receiving equipment, a light emission box located at an antenna end, a light receiving box at a receiving equipment side and the optical transmission media connected with the light emission box and the light receiving box, wherein radio frequency signals output by the antenna are transmitted to the light emission box through a cable, the light emission box converts the radio frequency signals into light signals and then transmits the light signals to the light receiving box through the optical transmission media, the light receiving box recovers the light signals to the radio frequency signals and then transmits the radio frequency signals to the indoor receiving equipment through a cable, and the indoor receiving equipment analyzes and processes the radio frequency signals. The radio frequency signals are converted into the simulating light signals for signal transmission, the transmission system is large in transmission bandwidth, large in capacity, small in chromatic dispersion and free of electromagnetic interference, loss of the signals on the transmission line is largely reduced, the signal quality, safety and reliability of the system are improved, and the construction cost is reduced.

The invention discloses a butterfly optical cable, which comprises a pair of reinforcing members and a main member. The pair of reinforcing members are arranged at the two sides of the main member. The side, close to the main member, of each reinforcing member is provided with a sharp edge. The sharp edges are connected with the main member through adhesion layers respectively; the sharp edges protrude to the inner sides of the main member; the sharp edges are connected with extension portions; the extension portions cover the outer surfaces of the reinforcing members; the sharp edges and the extension portions are made of a pressure-resistant material; the main member is internally provided with a foaming layer; the foaming layer is made of a foam material; the foam material is internally filled with nitrogen, nitrogen pressure being larger than or equal to 1.5 standard atmospheric pressure; an optical fiber is arranged in the foaming layer; and the radial height of the main member is smaller than or equal to that of the reinforcing member. Through the arrangement of the reinforcing members having the sharp edges and the extension portions, the pressure-resistant performance of the reinforcing members is better; meanwhile, the sharp edges are connected with the main member through adhesion layers respectively, so that the sharp edges can be separated from the main member more easily, and after separation, the main member forms two opposite grooves; and the optical fiber can be obtained by tearing away the foaming layer. The cable is simple to operate and excellent in protection performance.

The invention discloses a light switching apparatus, wherein a mobile support plate is provided two or more optical fiber connecting seats thereon, and each optical fiber connecting seat is respectively connected with an optical fiber path; and the mobile support plate is driven to move or to rotate by a driving device, to enable the optical fiber connecting seats on the mobile support plate to be switched to a corresponding position of an optical fiber connector and to enable the optical fiber connector to be fixed on one corresponding optical fiber connecting seat. The switches for different optical fiber paths can be achieved through a pure-mechanism type motion mode, and the apparatus is in no need of any optical element and has the advantages of simple structure, low cost, low signal loss, etc.

The invention discloses a minimized high-isolation ceramic packaging structure including a pipe case (a), a chip (b), a metal cover plate (c) and a bonding wire (d); the pipe case (a) is composed of a ceramic layer (a1), a metallization layer (a2) and an interconnection blind hole (a3); the metallization layer (a2) is composed of a bonding finger layer (a21), a sealing area (a22), a connection area (a23), a bonding chip area (a24) and a printed circuit board trace layer (a25); the pipe case(a) is provided in the center thereof with the bonding chip area (a24) for displacing the chip, and the circumference of the bonding chip area (a24) is provided with the bonding finger layer (a21) which includes a grounding bonding finger (a211) and a signal bonding finger (a212). The structure herein has the beneficial effects that stratum isolation technology is adopted, and space stereo-wrapping is conducted on the high-isolation bonding finger, and a space "sandwich" structure is formed; the structure can markedly reduce cross talk and coupling effect of the signal channels, reduce signal loss, increase isolation level, and reduce impact of packaging on the electrical property of the products, provided that the high reliability of the packaging is guaranteed by the structure.

The invention discloses a non-contact glass capillary diameter control method which comprises the following steps: depositing a fluorine-doped quartz low-refractive-index layer in a quartz base tube by using vapor deposition equipment, corroding and polishing the outer wall of the base tube by using hydrofluoric acid, and then drawing to manufacture a low-refractive-index quartz capillary; selecting a corresponding number of single-core optical fibers, removing coating layers of the single-core optical fibers through chemical corrosion, and inserting the plurality of single-core optical fibers into a low-refractive-index quartz capillary; using a tapering system for carrying out equal-proportion heat insulation tapering on the quartz capillary sleeve and the single-core optical fiber, thinning the quartz capillary, reducing the diameter at the taper waist to be equal to that of the multi-core optical fiber, and degrading the diameter of the internal single-core optical fiber to be matched with the fiber core of the multi-core optical fiber; measuring the tapering area, observing the diameter change of the tapering area, and cutting the tapering waist by using an optical fiber cutter to obtain a tapering body; and aligning and welding the cut cone and the multi-core optical fiber, and finally packaging to form the single-core optical fiber and multi-core optical fiber coupler.

The invention discloses an optical fiber end face pumping coupler preparation method based on a casing pipe method. An input signal optical fiber is prepared through a corrosion method, then a pumpingoptical fiber is prepared based on a tapering method, and an input signal optical fiber and all the pumping optical fibers are combined through the casing pipe method to form an optical fiber bundle.The optical fiber bundle is subjected to weak tapering, and the size of the fiber core of the input signal optical fiber is not changed in the whole weak tapering process. The end face of the opticalfiber bundle is cut to be flat and then is in low-loss welding with an output signal optical fiber. According to the invention, the pumping coupler based on any signal optical fiber and pumping optical fiber size can be realized, and the practical value of the pumping coupler is improved.

The invention provides a semiconductor package structure and a preparation method thereof. The semiconductor package structure comprises a redistribution layer; a flip-chip bonded to the lower surfaceof the redistribution layer; an electrical connection structure on the upper surface of the redistribution layer; a plastic package layer located on the upper surface of the redistribution layer andplastically packaging the electrical connection structure; a first antenna layer located on the upper surface of the plastic package layer; a frame structure located on the upper surface of the plastic package layer and located at the periphery of the first antenna layer; a cover plate on the top of the frame structure; a second antenna layer located on the lower surface of the cover plate; solderball bumps on the lower surface of the redistribution layer. The semiconductor package structure of the invention is reduced in volume, improves the integration degree of a device, has a short transmission signal path, and can obtain good electrical properties and antenna performance.

The invention discloses a special triangular cable for hole passing. The special triangular cable for hole passing comprises a core cable set, an outer-layer cable set and a protective shell, wherein the core cable set comprises two core cables; the outer-layer cable set is arranged on the outer sides of the core cables and comprises 12 outer-layer cables; a gap between the core cables and the outer-layer cables is filled with a polyethylene filled layer; a cable sheath wraps the outer side of the outer-layer cable set; and the protective shell sleeves the outer side of the cable sheath. The special triangular cable for hole passing is suitable for occasions such as a server with a limited internal space, has a larger core cross section per unit area, and has higher transmission efficiency than that of a traditional purely round cable. The invention also provides a manufacturing process of the special triangular cable for hole passing. The manufacturing process comprises the following steps: S1, manufacturing the cables, S2, arranging the cables, S3, wrapping with the cable sheath; and S4, manufacturing the protective shell. The manufacturing process can improve the internal insulating property and prevent the cable cores from mutual interference.

The invention discloses a preparation method for a grid of a RFLDMOS (radio frequency laterally diffused metal oxide semiconductor) device. A metal floating grid structure wrapping a grid and a drain is further prepared during preparation of a low-resistance metal grid, and is capable of effectively shielding high-frequency signals.

The invention discloses a soft board structure, a TO optical module and an optical transmission device, wherein the soft board structure comprises a first metal layer, a substrate and a second metal layer, which are stacked in sequence from bottom to top; the first metal layer is configured to provide a grounding plane; a high-speed signal link is formed on the second metal layer; a first high-speed signal through hole and a second high-speed signal through hole are formed on the soft board structure; a first through hole and a second through hole are respectively formed on the soft board structure and the position near the first high-speed signal through hole and the second high-speed signal through hole; and metal welding materials connected with the first metal layer are arranged on theside walls of the first through hole and the second through hole. When the soft board structure is assembled on the TO optical device, conductive materials connected to a tube socket and the metal welding materials are filled in the first through hole and the second through hole. The soft board structure, the TO optical module and the optical transmission device in the invention can be suitable for transmitting high-rate signals, and simultaneously, have a simple manufacturing process and relatively low manufacturing cost.