48results about How to "Suitable for long-distance transmission" patented technology

This invention discloses one infrared detector structure and process method based on micro mechanic bridge resonance device, wherein the detector is composed of bridge resonance chip and cover board through vacuum sealing technique or gas sealing technique; the incidence infrared line is to micro mechanic bridge surface through infrared incidence window to lead the bridge temperature rise and to add axis stress force and to lower resonance frequency to reflect incidence infrared strength.

The invention relates to a device for detecting the angular position and the speed of the switch magnetic resistance motor and method, comprising a rotary encoder and a signal processing circuit mounted in the motor and fixed on a support plate, wherein the rotary encoder is connected with the main axis of the motor. The rotary encoder collects and transfers the angular position signals of the rotator to the encoder signal pretreating unit of the signal processing circuit. The encoder signal pretreating unit converts the output signal of the encoder into the signal capable for being received by the microprocessor unit. The microprocessor unit processes the angular position signals and calculates the speed of the motor. The communication unit sends the angular position signals and speed signals by serial communication bus. The connection line of the said device with the outside is simple and the antijamming capability is strong. The device device for detecting the angular position and the speed of the switch magnetic resistance motor is suitable for long distance transmission with high resolution, easy operation, small error and no zero setting by manpower.

The invention discloses a photonic crystal optical fiber methane sensing device based on modular interference. The device is composed of a broadband light source, an optical circulator, a photonic crystal optical fiber methane sensor cladding an air hole coated polymer sensitive film, a testing air chamber, a switching valve, a quality flow controller, a spectrum analyzer and a computer, wherein the optical fiber methane sensor consists of a single mode fiber, a photonic crystal optical fiber and a welding area of the two fibers; the adopted photonic crystal optical fiber refers to an endless single mode solid core photonic crystal optical fiber; the polymer sensitive film refers to a polycarbonate resin methane sensitive film containing a cage molecule E-(OC2H5)6, and the inner wall of the cladding air hole of the photonic crystal optical fiber is coated with the film by virtue of an air pressure driving device; when the to-be-tested methane gas acts with the sensitive film on the inner wall of the cladding air hole of the photonic crystal optical fiber, the refractive index of the sensitive film changes, the reflection interference spectrum characteristic wavelength of the sensor is moved, the average movement amount shown in the description of the reflection interference spectrum characteristic wavelength before and after contacting the sensor with the methane gas is analyzed, so that the concentration of the to-be-tested methane gas can be obtained. The device disclosed by the invention has the characteristics of high sensitivity, high stability, high selectivity and the like.

The invention discloses an all-optical single side band (SSB) up conversion generator based on a silicon-based micro ring resonator, comprising a central station and a base station, wherein the central station is composed of a pumping signal optical generating system, a tri-frequency component detection signal optical generating system, a silicon-based micro ring resonator system, a first optical amplifier, an adjustable narrow-band filter and an uplink data receiver; and the base station is composed of an optical fiber bragg grating, a photoelectric detector, a first Mach-Zehnder modulator and an uplink data source. The invention injects pumping light in a silicon-based micro ring to generate a free carrier, and the silicon-based micro ring resonance peak is subjected to blue shift due to the dispersion effect of the free carrier, so as to modulate signals on detection light to realize the all-optical single side band (SSB) up conversion. The used device has small volume and is easy to integrate; and the used SSB modulation is influenced small by optical fiber dispersion, the system cost is reduced and the system structure is simplified due to the characteristics of quad-frequency technology and needless of an uplink light source of the base station.

The invention discloses a portable cell incubator. The portable cell incubator comprises an incubator body provided with a sample culture area, and a circuit control device, wherein the circuit control device comprises a microcontroller, a temperature control device, and a humidity control device. The internal space of the incubator box is partitioned into a water cooling zone, an ultrasonic humidification water consumption zone and an ultrasonic humidification zone by a division plate; the temperature control device is used for setting different temperature values through a keyboard input device, and can adapt to temperature values required by culturing and preserving cell samples in different cases; and the humidity control device comprises a humidity sensor, an ultrasonic atomization humidifier and a humidity control circuit. In the incubator, a semiconductor chilling plate is used for raising and reducing temperature and humidification is realized by ultrasonic atomization, and control parameters of the culture area are regulated and controlled in real time by utilizing data measured by the sensor, so that constant temperature and constant humidity are realized; a lead storagebattery is adopted to supply electricity, so the incubator can steadily work for a long time; and the incubator has a smaller volume and light weight, is convenient to carry, and is suitable for remote transmission.

The invention discloses a rope transmission device, which is characterized in that a rope is arranged on circumferential edge parts of a driving wheel and a driven wheel in a tension way, the friction force between the rope and each wheel body is increased by additionally arranging a plurality of driving auxiliary wheels and driven auxiliary wheels, and the rope can be taken up and paid off on each wheel body along the rotation of each wheel body, so that the power transmission between the driving wheel and the driven wheel is realized. Compared with the belt transmission or the chain transmission adopted in the prior art, the rope transmission device has a simple structure, low installation precision, low cost and smaller size of the device; and compared with a method that the friction is increased by winding multiple circles of rope on each wheel body, the rope transmission device is free from causing the seizure of the rope being squeezed and wound in the axial direction when the wheel bodies rotate. The rope transmission device has good application performance and is more suitable for the remote transmission which does not need the large power.

The invention discloses a terahertz signal generation method and device, and a computer readable storage medium, and the method comprises the steps: obtaining a mixed transmitting signal correspondingto a radar transmitting signal and a communication transmitting signal, and obtaining a first optical signal and a second optical signal which are generated by an optical frequency comb and have coherence; modulating the mixed transmitting signal into the optical wavelength of the first optical signal through a first single side band modulator to obtain a third optical signal; coupling the thirdoptical signal with the second optical signal through a combiner connected with the first single side band modulator to obtain a coupling signal; and performing photoelectric frequency mixing on the coupling signal through a first photoelectric converter connected with the combiner so as to convert the coupling signal into a terahertz signal. According to the invention, the long transmission distance performance of terahertz signals is improved.

The invention provides a notched jade ring type circular polarized antenna. The circular polarized antenna comprises an antenna unit and an earth plate, and is characterized in that the antenna unit conducts single feeding through a coaxial feeder; a sector is cut in the surface of the annular antenna unit; the center of the sector and the center of the antenna unit are at a same position; the radius of the sector is equal to the outer diameter of the antenna unit; air dielectric is arranged between the antenna unit and the earth plate. The circular polarized antenna has the advantages that the circular polarized antenna is simple in feeding manner, relatively low in influence of change of feeding point position to aerial performance, and relatively wide in band frequency.

The invention discloses a vehicle-mounted wireless video interaction transmission system for traffic accident surveying vehicles. The vehicle-mounted wireless video interaction transmission system comprises a vehicle-mounted terminal of a traffic accident surveying vehicle, a wireless transmission device and a command center server terminal, wherein the vehicle-mounted terminal of the traffic accident surveying vehicle converts video image analog signals into an accident collection field into video image digital signals; the wireless transmission system sends the digital signals to a 3G (third generation) wireless network; and the command center server terminal receives the digital signals sent by a wireless transmission device through a network butt joint module according to the preset network safety requirements, and feeds back to the vehicle-mounted terminal of the traffic accident surveying vehicle through the network butt joint module so as to achieve the effect of information interaction transmission. Based on the 3G wireless network, the embodiment of the invention takes a WCDMA (wideband code division multiple access) and a CDMA (code division multiple access) 2000 as main carriers, and has the advantages of good confidentiality, interference resistance, multipath fading resistance, flexible configuration, low cost and the like; and in the aspect of a wide band, the WCDMA and the CDMA2000 meet the requirement of transmission after the compression of high-definition video signals, and has a transmission mode of several-for-one.

The invention discloses a high-power semiconductor laser surface treatment device for the inner walls of large long barrels. The device comprises a laser generation assembly, a laser beam expander anda laser processing beam type central rotating shaft, wherein the laser processing beam type central rotating shaft is arranged in a to-be-processed pipe fitting during use, and is provided with a shaft internal light guide channel; laser is transmitted through the shaft internal light guide channel after being shaped by the laser beam expander; a translation machine frame is further arranged in the laser processing beam type central rotating shaft, can rotate along with the rotation of the laser processing beam type central rotating shaft, and is used for driving a focusing assembly and a laser turning mirror to horizontally move in the laser processing beam type central rotating shaft; and the length of the to-be-processed pipe fitting is more than 10 meters. For the inner walls of largelong barrel workpieces such as ocean equipment, oil transportation pipelines, chemical equipment, tunneling equipment, coal mining equipment and the like, a high-power semiconductor laser cladding technology is used for enhancing the performances such as the wear resistance, the corrosion resistance and the like of the surfaces of the inner walls of the selected workpieces, so that the service lives of the workpieces are greatly prolonged.

The invention discloses a multichannel optical module and an optical fiber communication system, relates to the technical field of optical fiber communication and is used for solving problems in the prior art that the multichannel parallel processing ability is low and that an optical path and the optical transmission efficiency at the junction of optical signals and an optical fiber are not considered. The multichannel optical module is characterized in that a light transmitting assembly, a light receiving assembly and an FPGA chip are arranged inside a shell, and first optical fiber collimators and second optical fiber collimators are arranged outside the shell; a single path of transmitting electric signals are converted into multiple paths of transmitting electric signals through the FPGA chip, the light transmitting assembly simultaneously receives the multiple paths of transmitting electric signals and transmits multiple paths of transmitting light signals, the multiple paths of transmitting light signals are transmitted to multiple paths of optical fibers through the first optical fiber collimator group; the light receiving assembly receives multiple paths of receiving light signals transmitted by the multiple paths of optical fibers through the second optical fiber collimator group and transmits multiple paths of receiving electric signals, and the FPGA chip simultaneously receives the multiple paths of receiving electric signals and converts the multiple paths of receiving electric signals into a single path of receiving electric signals. The invention further discloses an optical fiber communication system.

The invention relates to one transmission device with multiple base color visual signals transmission automatically calibration system, which comprises emission part and receive part circuits, wherein, in transmission, emission part directly emits signals and the receive part receives transmission signals according to stored calibration signals; when user sends order, system enters calibration mode with first signals; then receive part sends correction order and according to partly correction sequence signals, the receive part tests correction signals as each visual signal balance process and simultaneous time lag signal process then storing correction parameters.

The invention discloses an information collecting system which comprises an RFSN node and an aggregation node. The RFSN node is used for reading label information and collecting environment information and can communicate with the aggregation node, and the aggregation node is used for creating a communication network to communicate with the RFSN node and sending obtained information to an upper computer. The RFSN node is provided with a microcontroller, a reader transceiver, an RF transceiver, a sensor, a power source and a control module of the power source. The aggregation node is provided with a ZigBee module and a serial port communication module. The RFSN node is used for reading label information through the reader transceiver and carrying out network communication through the RF transceiver, so that flexible networking is facilitated, and the FRSN node is suitable for long-distance transmission; the reader transceiver and the RF transceiver are integrated in one node and internally communicate through the microcontroller, communication speed is greatly improved, and information distortion and mismatching in communication are lowered due to the fact that the microcontroller integrates information of the reader transceiver and information of the sensor.

A high-speed memory array structure based on a SATA interface solid state drive uses the SATA interface solid state drive (1) composed of a NAND FLASH array, a control unit (6) and a SATA interface protocol (4) as a disk array, the RAID disk array of a standard rack construction is connected with a SATA RAID controller (2), and a Fibre Channel interface (3) in accordance with the fiber channel communication standards is connected with the SATA RAID controller (2) to realize the high-speed solid-state memory array. The memory array with the solid-state disk as a memory medium greatly expands the application range and the service life of the memory array. The transmission cable of the optical interface expands the transmission distance.

The invention relates to a multiplex pulse synchronization method based on optical fiber transmission, and mainly solves the problems in an existing pulse synchronization technology that synchronization performance is poor on an aspect of long-distance transmission, and implementation cost is lowered. The implementation process of the method comprises the following steps that: 1: a pulse sending plate FPGA (Field Programmable Gate Array) utilizes a reference clock to generate a pulse signal, a special character represents a pulse signal, and the pulse signal is sent out through multiple pathsof equal-length optical fibers; 2: after each pulse receiving plate detects the special character in the optical fiber data, the original pulse signal is recovered; 3: the position of the recovered pulse is regulated, the rising edge of the regulated pulse is positioned on the middle position of the recovered pulse, the reference clock is used for latching the regulated pulse, and a final synchronous pulse is obtained. By use of the method, the problem that the pulse is not synchronous due to clock jitter is solved, the equal length optical fiber is used for transmitting the synchronous pulsesignal, and the optical fiber data transmission technology is mature and stable, is suitable for long-distance transmission, is simple in implementation on the basis of the FPGA, and is easy in engineering implementation.

The invention provides a carrier synchronization method and system during parallel operation of multiple converters. The method comprises the following steps: modulating an original synchronization signal sent by a master controller in a plurality of converters by using a modulation wave signal to obtain a carrier synchronization clock signal, and transmitting the carrier synchronization clock signal to each slave controller in the plurality of converters to perform carrier synchronization, wherein the frequency of the modulated wave signal is lower than that of the original synchronous signal, and the modulated carrier synchronous clock signal is consistent with the modulated wave signal in frequency, so that the frequency of the carrier synchronous clock signal is lower than that of theoriginal synchronous signal, and the carrier synchronous clock signal is suitable for long-distance transmission. Compared with the scheme of carrying out carrier synchronization by using the communication conversion module, the scheme of the invention does not need to transmit a synchronization signal while transmitting a conventional signal, so that the influence on a software architecture and communication pressure is reduced.

The invention provides a PCIE signal transmission method, which refers to communication field, and can improve transmission efficiency, reliability, save design cost, and is suitable for long-distance transmission. The method comprises the steps of generating a PCIE electric signal to be transmitted to an opposite-end apparatus, wherein the opposite-end apparatus is an apparatus excludes from the PCIE electric signal generating apparatus; converting the generated PCIE electric signal into a PCIE optical signal; and transmitting the PCIE optical signal to the opposite-end apparatus. The invention also provides corresponding apparatus.

A device applying optical fiber communication technique on data communication of photoelectric theodolite consists of orientation shaft, the first and the second connection frames, the first and the second optical collimator tail fibers, the first and the second optical collimator tube shells, the first and the second optical collimator lens sets and base of theodolite. The device not only can raise transmission rate but also can avoid electromagnetic-wave interference on signal.

The invention provides a radial displacement sensor and a rotor radial displacement detection system of a magnetically levitated molecular pump. The displacement sensor comprises a detecting unit and an adjusting unit, wherein the adjusting unit is used for adjusting the voltage amplitude of the output signal of the radial displacement sensor according to the difference of processing and assemblyaccuracy between different parts of the magnetically levitated molecular pump. The rotor radial displacement detection system of the magnetically levitated molecular pump comprises the radial displacement sensor. The radial displacement sensor is arranged in a pump body, and a demodulating unit and a processing unit are arranged in a controller, thus realizing the interchangeability between the magnetically levitated molecular pump and the controller; and meanwhile, the signal-to-noise ratio of the output signal of the radial displacement sensor during remote transmission can be improved, thus ensuring the signal quality.

The invention relates to the technical field of a microwave antenna, and specifically relates to an E-band high-performance antenna, comprising a reflective surface, an antenna cover and a feed source; the feed source comprises a feed source base, a waveguide tube, radiation dielectric and a secondary reflective surface; a through hole is formed in the central position of the feed source base; a waveguide port is formed in one, positioned on the exterior of the reflective surface, of the through hole, and the waveguide tube is inserted in one end positioned in the inner cavity of the reflective surface; the radiation dielectric adopts a T-shaped structure, and comprises lower part dielectric inserted in the waveguide tube and opposite to one end of the feed source base, and upper part dielectric arranged on the exterior of the waveguide tube; an annular groove is formed in the outer edge of the lower part dielectric; at least one layer of annular stage is arranged on the outer edge ofthe upper part dielectric; a conical groove is formed in the end plane, opposite to the lower part dielectric, of the upper part dielectric; and the secondary reflective surface is matched with the conical groove in shapes and attached in the conical groove. The E-band high-performance antenna is simple and convenient to mount, easy to produce, low in cost, low in dielectric loss and high in frequency band.

The invention relates to a breakage-resistant optical cable, which comprises a reinforcing core, a cable core, a cable core filler, a coated aluminum strip and a polyethylene sheath. The aluminum strip covers the cable core, and the gap between the reinforcing core and the cable core and between the cable core and the coated aluminum strip is filled with cable core fillers, and the polyethylene sheath covers the coated aluminum strip; The core includes an optical fiber, a tube filler and a loose tube. The loose tube covers the optical fiber, and the gap between the fiber and the loose tube is filled with the tube filler; multiple "I" shapes are embedded in the loose tube. The ribs, the roughness of all surfaces of the ribs are <0.4μm. The invention has the advantages of high strength, bending resistance, good tensile resistance, good toughness and long service life, and has very little attenuation in the signal transmission process, and is suitable for long-distance transmission.

The invention relates to the technical field of communication equipment, in particular to optical fiber relay remote equipment, which comprises an optical fiber relay far-end machine and an optical fiber relay far-end machine, the optical fiber relay far-end machine realizes signal transmission with the optical fiber relay far-end machine through an optical cable; the optical fiber relay pull far-near end machine comprises a first duplexer, a first power amplifier, a second power amplifier, a first monitoring board and a first optical module. The optical fiber relay remote terminal comprises asecond duplexer, a third power amplifier, a low-noise amplifier, a second monitoring board and a second optical module; base station signals are output through the optical fiber relay remote device,then the signals are transmitted out through the retransmission antenna, and meanwhile the retransmission antenna can receive the signals transmitted by the interphone and transmit the signals to thebase station through the optical fiber relay remote device. Compared with a base station, the method has the advantages of low cost and fast construction, and is suitable for large-scale scenes.

The invention discloses a system and method for judging fan tower deformation and foundation settlement, and the system acquires the temperature change data, displacement change data and strain changedata of a fan tower and a fan bottom foundation of a wind turbine generator in real time through a fiber bragg grating sensor, a fiber bragg grating wavelength demodulator is utilized to demodulate the data, and the demodulated data is then sent to a monitoring server so as to visually display the demodulated temperature change data, displacement change data and strain change data, thereby judging the deformation and foundation settlement of the fan tower. According to the invention, dynamic measurement can be realized, and the system has the advantages of strong anti-electromagnetic interference capability, good insulation, corrosion resistance, high precision, large-range measurement, high resolution, small size, light weight, strong capability of adapting to a measured environment, many measurable parameters, wide objects, strong compatibility with optical fibers, suitability for long-distance transmission, high sensitivity, and convenience for multiplexing and networking.

A device applying optical fiber communication technique on data communication of photoelectric theodolite consists of orientation shaft, the first and the second connection frames, the first and the second optical collimator tail fibers, the first and the second optical collimator tube shells, the first and the second optical collimator lens sets and base of theodolite. The device not only can raise transmission rate but also can avoid electromagnetic-wave interference on signal.

The invention discloses a photonic crystal optical fiber methane sensing device based on modular interference. The device is composed of a broadband light source, an optical circulator, a photonic crystal optical fiber methane sensor cladding an air hole coated polymer sensitive film, a testing air chamber, a switching valve, a quality flow controller, a spectrum analyzer and a computer, wherein the optical fiber methane sensor consists of a single mode fiber, a photonic crystal optical fiber and a welding area of the two fibers; the adopted photonic crystal optical fiber refers to an endless single mode solid core photonic crystal optical fiber; the polymer sensitive film refers to a polycarbonate resin methane sensitive film containing a cage molecule E-(OC2H5)6, and the inner wall of the cladding air hole of the photonic crystal optical fiber is coated with the film by virtue of an air pressure driving device; when the to-be-tested methane gas acts with the sensitive film on the inner wall of the cladding air hole of the photonic crystal optical fiber, the refractive index of the sensitive film changes, the reflection interference spectrum characteristic wavelength of the sensor is moved, the average movement amount shown in the description of the reflection interference spectrum characteristic wavelength before and after contacting the sensor with the methane gas is analyzed, so that the concentration of the to-be-tested methane gas can be obtained. The device disclosed by the invention has the characteristics of high sensitivity, high stability, high selectivity and the like.

The invention provides an intelligent electricity grid, which comprises an optical-signal transmitting master station, a power-generation master station, a transformer station, a comprehensive treatment center, intelligent distribution terminals and use terminals, wherein optical signals transmitted by the optical-signal transmitting master station and electric energy of the power-generation master station are simultaneously transmitted to the transformer station through composite optical cables formed by glass optical fibers and cables, and are transmitted to the comprehensive treatment center after electric power distribution through the transformer station; and the electric energy transmitted through the composite optical cable is optimized in the comprehensive treatment center, the optical signals carried by the glass optical fibers are accessed to the Internet to carry out optical signal processing, and then the electric energy and the processed optical signals are transmitted to the intelligent distribution terminals through the composite optical cables formed by glass optical fibers and cables, and are simultaneously transmitted to the corresponding use terminals by the intelligent distribution terminals through plastic optical-fiber bunched optical cables integrated by plastic optical fibers and cables. The intelligent electricity grid provided by the invention has the advantages of low cost, high efficiency, and simpleness and easiness in maintenance.

The invention discloses a long-distance PCIe extension system and a data transmission method of the long-distance PCIe extension system. The long-distance PCIe extension system comprises a host end interface device, an extension line and an equipment end interface device, wherein the host end interface device is in the disguise of PCIe equipment according to the configuration information, sent by the equipment end interface device, of the PCIe equipment; the equipment end interface device is in the disguise of a host according to received commands; and the extension line is a high-speed connecting line and is used for receiving and sending data between the host end interface device and the equipment end interface device according to a user-defined format. According to the long-distance PCIe extension system and the data sending method of the long-distance PCIe extension system provided by the invention, an embedded system is adopted; an FPGA (Field Programmable Gate Array) does not need to be adopted for carrying out conversion on a PCIe protocol; and the system and the method have the beneficial effects of simple and convenient design and low cost, and are suitable for long-distance transmission.

The invention discloses a hand-made Chinese-style gift box. The hand-made Chinese-style gift box comprises a box body of a regular hexahedron structure, wherein a pastry box, four ball supports and eight egg supports are fixed on the bottom surface of the box body; the pastry box is positioned in the center of the bottom surface; the four ball supports are uniformly distributed around the pastry box; two egg supports re uniformly distributed between every two adjacent ball supports; the distances between the ball supports and the pastry box, as well as between the egg supports and the pastry box, are equal; a red bamboo tube is fixed on the inner wall of each of the four side surfaces of the box body; a candle box is fixed at each of the four corners of the box body; and the pastry box, the four ball supports, the eight egg supports, the red bamboo tubes and the candle boxes are all positioned in the box body. Fixing devices which can fix objects placed in the gift box are arranged in the gift box, the objects placed in the gift box have very good blessing meanings, and the hand-made Chinese-style gift box is applicable to long-distance transmission.

The invention discloses an airflow cotton conveying device. The device comprises a cotton conveying pipe, a cotton conveying pipe inlet and a cotton conveying pipe outlet which are formed at two ends of the cotton conveying pipe, a fan, a dust cage which is arranged in the cotton conveying pipe and a leather bladed beater, wherein the leather bladed beater is arranged below the dust cage; and the fan is arranged in front of the cotton conveying pipe inlet. The invention solves the problem that: in the prior art, cotton flow passes through a cotton conveying device and then is still required to pass through a cotton condenser so as to remove impurities, such as dust, flocks and the like, in cotton, so that the processes are more complicated, and the long-distance conveying of the cotton is unfavorable; the dust cage is arranged in the cotton conveying pipe, and the fan is used for producing negative pressure in the dust cage, so that the impurities such as the dust, the flocks and the like pass through small holes in the surface of the dust cage and enter the dust cage, and the cotton conveying pipe removes the impurities when conveying the cotton; and the device has a simple structure, is low in cost and high in transmission speed, and is applicable to long-distance conveying.

The invention discloses an all-optical single side band (SSB) up conversion generator based on a silicon-based micro ring resonator, comprising a central station and a base station, wherein the central station is composed of a pumping signal optical generating system, a tri-frequency component detection signal optical generating system, a silicon-based micro ring resonator system, a first opticalamplifier, an adjustable narrow-band filter and an uplink data receiver; and the base station is composed of an optical fiber bragg grating, a photoelectric detector, a first Mach-Zehnder modulator and an uplink data source. The invention injects pumping light in a silicon-based micro ring to generate a free carrier, and the silicon-based micro ring resonance peak is subjected to blue shift due to the dispersion effect of the free carrier, so as to modulate signals on detection light to realize the all-optical single side band (SSB) up conversion. The used device has small volume and is easy to integrate; and the used SSB modulation is influenced small by optical fiber dispersion, the system cost is reduced and the system structure is simplified due to the characteristics of quad-frequency technology and needless of an uplink light source of the base station.