222 results about "Channel simulator" patented technology

The invention discloses a V2X Internet of Vehicles (IoV) on-loop simulation system, and belongs to the field of IoV. The system is mainly composed of an IPG carmaker IoV simulation platform (01), a Simulink environment module (02), a channel simulator (03), a V2X communication terminal (04) and a V2X road side device (05), wherein the IPG carmaker simulation tool is responsible for building a simulation scene and configuring simulating parameters, the Simulink environment module is responsible for building a channel model, a simulation scene and real scene mapping model, a control model and acommunication model, the channel simulator is used for conducting performance test on LTE-V, 802. 11p communication protocol, the V2X communication terminal is connected with the Simulink communication model to obtain the scene information and realize on-loop simulation, and the V2X road side device imports the obtained information of the real scene into a simulation scene to achieve an outdoor test function. All the modules supplement each other to form a perfect on-loop simulation system and provide a good testing and verifying platform for the IoV application.

The present invention relates to a method and a simulator for simulating an RF channel between a radio transmitter and a radio receiver located at a far distance from one another, in which radio channel multipath propagation occurs, and with which simulation at least part of the phenomena caused by the multipath propagation to the radio signal, such as delay spread, attenuation and Doppler shift are implemented. As taught by the method, an RF signal (fin) is moved to a lower frequency (fIF), and from said lower frequency signal (fIF) thus produced samples are taken and written in a memory at a predetermined write frequency (fw). The stored samples are read from the memory after a period of time of the length of the propagation delay (tDi) of each propagation path (i) to be simulated from the storage in the memory at a read frequency (fPi) predetermined for each propagation path (i) to be simulated, said read frequency differing from the write frequency (fw), when the frequency difference ( DELTA f01) of said write frequency (fw) and the propagation-specific read frequency (fRi) represent the Doppler shift of the frequency occurring in each propagation path (i).

The invention discloses a high dynamic satellite channel simulator, belonging to the field of satellite communications. The satellite channel simulator comprises a channel parameter generation unit, a channel simulation unit and a radio frequency unit. The whole system has the following working principle: a computer operates satellite channel simulation software, a satellite channel model, a communication frequency point, orbit parameters, terminal parameters and environmental parameters are configured, and a simulation program is started after configuration is completed. In the operating process of the simulation program, generated channel parameters are transmitted to the satellite channel simulation unit via the Ethernet network, the simulation unit loads the satellite channel parameters to a signal sent by a satellite communication device, the realization of channel simulation is completed, and finally, the radio frequency unit modulates the signal to radio frequency. The invention has the main goal of accurately and timely simulating a satellite channel under laboratory conditions, and a channel simulator with controlled cost and strong operability is provided for the development of the satellite communication device.

The present invention discloses a method and an apparatus for testing (TIS) in a multi-antenna (MIMO) system. The apparatus includes a base station simulator, a multipath fading channel simulator and a darkroom including a measuring antenna and a device under test placed in the darkroom. During the testing, the base station simulator generates transmitting signals of multiple transmitting antennas, and the transmitting signals have characteristic of orthogonal polarization and adopt STBC or SFBC; the multipath fading channel simulator adds corresponding channel parameters and noise interference parameters to the transmitting signals, and transmits the transmitting signals which have been decayed to the measuring antenna in the darkroom to send the transmitting signals which have been decayed to the device under test; the device under test performs multi-antenna receiving on the transmitting signals, performs MRC on received signals, and acquires the (TIS) according to the received signals which have been combined.

An output signal of digital baseband processing section 41 is directly input, and receiver noise adding section 103 adds receiver noise simulating the SNR variation due to fading to the signal while keeping an entire signal level constant in single-path channel simulation, while in multipath channel simulation, instantaneous variation adding section 101 and short-term interval variation adding section 102 add only amplitude variations to respective signals of paths, and automatic gain control section 104 keeps a level of the path-combined signal constant, whereby it is possible to evaluate channel performance of digital baseband processing section 41 without waiting for development of radio circuit 53, i.e. without an AGC circuit and AFC circuit in reception system 50.

The invention discloses a space radio-frequency performance test method and a system in a multi-antenna system. More than two antennas are arranged on a dark absorbing chamber; a base station simulator is controlled to send a reference test signal to a device to be tested through a channel simulator and an antenna; when the reference test signal is determined to not satisfy set requirements, the reference test signal is adjusted until the set requirements are satisfied; corresponding test cases are determined according to different channel models; signal simulation is implemented by a channel emulator on the test signal outputted by the base station simulator, and then the test signal is sent to the device to be tested through the antenna; each radio-frequency performance of the device to be tested after the receiving of the test signal is tested according to the radio-frequency performance test items corresponding to the test cases; and when all the radio-frequency performances reach the standard, the space radio-frequency performance reaches the standard. The invention also discloses a space radio-frequency performance test system in the multi-antenna system. The invention is simple to realize and has lower cost.

The embodiment of the invention provides a double-darkroom structure for an MIMO OTA test and a test method. The double-darkroom structure comprises a first darkroom, a second darkroom, a third darkroom and a fourth darkroom, wherein the first darkroom comprises a first tested device and a first group of probes which are respectively arranged in the first darkroom according to a real environment simulated by a first tested device, are arranged in a non-contact manner and transmit a first signal in a radiation manner. The second darkroom comprises a second tested device and a second group of probes which are respectively arranged in the second darkroom according to a real environment simulated by the second tested device, are arranged in a non-contact manner and transmit a second signal ina radiation manner. The channel simulator comprises a channel port on one side and is connected with the first group of probes through a first radio frequency wire penetrating through the first darkroom, and the channel port on the other side and contained in the channel simulator is connected with the second group of probes through a second radio frequency wire penetrating through the second darkroom.

Provided is a simulation drive test method for a TD-LTE system. First, SINR and RSRP of a drive test terminal test and statistics drive test transmission line are used in a practical TD-LTE network environment, sampling is carried out at a set cycle, sampling values are stored, and then the sampling values are transmitted to a computer; the computer processes the sampling values, wherein RSRP and SINR between the two sampling values are filled up at the minimum cycle which can be identified by a channel simulator, and then the channel simulator connected between an indoor base station and a terminal is introduced; an outer field practical transmission line simulation environment is achieved indoors, wherein noise is added into the channel simulator, so that SINR which passes through the channel simulator and SINR which is recorded practically in an outer field are identical or similar in numerical value and changing trend; and then according to reference signal receiving power, output signal power of the channel simulator is controlled, so that indoor testing of the terminal can have the same or similar performance as outer field testing. According to the method, manpower, material resources, financial resources and time cost of outdoor scenario test are greatly saved, problem reappearing is convenient, and a test process is simplified.

The invention discloses a test method and device of total isotropic sensitivity (TIS) in a multi-antenna multi-input multi-output (MIMO) system. The test device comprises a base station emulator, a multipath fading channel simulator and a darkroom, wherein the darkroom comprises test antennas and a tested device, wherein the test antennas and the tested device are arranged in the darkroom. When the device is used for testing the TIS, the base station emulator generates emission signals of multiple transmitting antennas, wherein the emission signals have cross polarization characteristics and adopt space-time codes or space-frequency codes; the multipath fading channel simulator adds corresponding channel parameters and noise interference parameters to the emission signals, and transmits the faded emission signals to the test antennas in the darkroom so as to transmit the faded emission signals to the tested device; and the tested device performs multi-antenna receiving on the emission signals, and carries out maximum ratio combining (MRC) on the received signals as well as acquires the TIS in accordance with the combined received signals. According to the invention, the test of the TIS in the multi-antenna MIMO system can be realized.

The invention provides a multi-mode mobile satellite communication verification system and verification method. The system comprises a terminal simulator, a user link channel simulator, a receiving multi-beam antenna simulator, a return link processor, a subband exchange processor, a signal regeneration processor, a forward link processor, a transmitting multi-beam antenna simulator, a feeder link channel simulator, a gateway station simulator and a control center, a user segment, a space segment, a ground segment and a mobile satellite communication channel of a mobile satellite communication system are separately simulated. The system can perform demonstration verification on the link performance and the business ability of the mobile satellite communication system adopting a plurality of satellite-borne processing modes and multiple communication systems, and solves the problem that related verification system and method is lacked at present and technical feasibility verification cannot be provided for engineering application. Meanwhile, the invention further discloses a verification method of the verification system.

The invention discloses an antenna testing system which comprises a signal transmission simulator, a channel simulator and a wave absorbing chamber, wherein at least two antennas are arranged in the wave absorbing chamber, the antennas are connected with the signal transmission simulator through the channel simulator and used for providing at least two paths of transmitting signals to equipment to be tested; the two antennas are positioned on a spherical surface taking the position of the equipment to be tested as the centre of sphere. Simultaneously, the invention also discloses an antenna testing method on the basis of the testing system. More than one testing channel model are arranged in the signal transmission simulator. A channel model is selected from the channel models, a wireless signal is transmitted according to the selected channel model and simulated by the channel simulator, and then the simulated wireless signal is transmitted through the antennas in the wave absorbing chamber; and the equipment to be tested which is arranged in the wave absorbing chamber receives the transmission signals of all the antennas, processes the signals and outputs the processing result. The antenna testing system and the testing method are easy to realize and have lower cost.

This invention discloses a multi-path decline test system and a method for terminals of the mobile communication network including a noise interference signal simulator connected with the tested mobile terminal, a RF channel simulator connected with the noise interference signal simulator, a radio combined tester connected with the two simulators, in which, a quality certification control device is connected with them via GPIB cable and transmits the control signals and test data via GPIB bus.

The invention discloses a wideband wireless channel simulator and a relative method, wherein the device comprises at least one signal channel, a computer controller, a computer, and a channel data exchanger. The signal channel receives and sends radio signal, the computer controller receives and buffers the channel parameter and control command generated by the computer, and transfers data to each signal channel, the computer bears an operation module simulated by the wideband wireless channel, while the operation module generates channel data and communicates with the computer controller, and the channel data exchanger exchanges data between signal channels. The invention can realize quick and accurate simulation of wideband channel, particularly for simulating the condition which uses antennas to send and / or receive signal transmitted in wireless channel. The inventive device has simple structure and easy application.

An intermediate frequency equivalent low-earth-orbit satellite mobile channel simulator with channel switching control relates to the field of satellite communication. The invention settles the problem that no low-earth-orbit satellite mobile communication channel simulator which maximumly approaches the real channel does not exist at present. The intermediate frequency equivalent low-earth-orbit satellite mobile channel simulator with channel switching control is composed of an uplink channel simulator and a downlink channel simulator. Three input ends of the uplink channel switching control part of the uplink channel simulator are user terminal signal input ends. Six signal output ends of the uplink channel switching control part are respectively connected with the signal input ends of six uplink channel fading characteristic simulation parts. The signal output ends of six uplink channel fading characteristic simulation parts are satellite beam output ends. The simulation signal output ends of the uplink simulation control proxy part is simultaneously connected with the input end of the uplink channel switching control part and the input ends of six uplink channel fading characteristic simulation parts. The process of the downlink channel simulator is the reverse process of the uplink channel simulator.

This invention relates to analogue wireless multi-path declining signal device, which is characterized by the following: the declining signal generation is based on multi-sampling signal process structure and it reads the declining signals through Doppler frequency displacement pre-stored in the memory unit and controls the reading speed of each path to realize the sampling operation to get the parallel output of the maximum Doppler frequency displacement; the signal division and lag processed in one multi-path digital lag and generating signal channel mode with different lag power structure through server series double RAM initial writing address and several path selector.

The invention discloses a testing system for radio frequency consistency of a satellite mobile communication terminal and a testing method of the testing system. The system comprises a logic channel information generator, a frequency correction channel modulation module, another service and control channel modulation module, a channel multiplexing module, a radio frequency up-conversion module, a satellite-to-ground channel simulator, a duplexer, an attenuator, a radio frequency down-conversion module, a channel demultiplexing module, a terminal random access channel demodulation module, a terminal service data channel information acquisition module and a radio frequency consistency testing module. The testing system constructs a satellite-to-ground channel environment by matching the satellite-to-ground channel simulator with the radio frequency up-conversion module, the radio frequency down-conversion module and the attenuator, and simulates a ground station to test the satellite mobile communication terminal. The testing system tests the radio frequency consistency of the satellite mobile communication terminal, is simple in structure and easy to realize, and can lower the testing cost, thereby promoting industrial development of satellite mobile communication.

The invention discloses a test device and method, which are used for testing performance of a system composed of a base station and user equipment (UE) under different simulated scenes. The test device comprises a channel simulator, a parameter configuration unit and an electrical control unit, wherein, the channel simulator is used for realizing a connection between the base station and the UE under the current simulated scene; the parameter configuration unit is used for configuring parameters related to the base station and the UE under the current simulated scene and determining attenuation amount of signals between the current base station and UE according to the parameters; and the electrical control unit is used for adjusting the attenuation amount of the signals between the base station and the UE by adjusting the voltage or current input to an electric control attenuator corresponding to a channel between the base station and the UE in the channel simulator according to the attenuation amount of the signals between the current base station and UE, thus achieving the purpose of testing the system performance corresponding to the current simulated scene.

The invention provides a broadband satellite channel simulator with a variable channel model. The broadband satellite channel simulator comprises an analog-signal conversion module, an input signal amplitude adjustment module, a channel delay simulation module, a channel fading simulation module, a channel noise simulation module, an output signal amplitude adjustment module, a digital-analog conversion module and an upper computer control module. According to the channel simulator, problems of narrow input bandwidth, low carrier rate, delayed channel model parameter updating and poor input and output port extensibility of the existing channel simulator can be solved; and physical simulation and communication system verification of all kinds of broadband satellite communication programs can be supported effectively.

The invention provides a wireless terminal performance test method and a wireless terminal performance test device. According to the method, a performance test on an LTE-V2X terminal under an anechoicchamber environment is achieved. Firstly, a test system including an anechoic chamber, and first test equipment, a sending end, a channel simulator, an adjustable attenuator, a receiving end and second test equipment connected in sequence along a signal transmission direction in the anechoic chamber is built. When a test is performed, a signal propagation path loss value under a scene is determined according to channel models corresponding to the different scenes, when a signal propagation path loss value can be simulated by the channel simulator cannot reach the signal propagation path lossvalue needed by the scene, the actual signal propagation path loss value under the scene is simulated by the sum of the signal propagation path loss value of the channel simulator and an attenuation value of the adjustable attenuator, a simulated path loss range is increased, and the problem that when a performance test is performed in a laboratory, the channel simulator cannot simulate the signalpropagation path losses under all the scenes is solved.

The invention provides a device for measuring bit error rate of communication equipment, which consists of programmable process equipment 1, user-controlled software and a signal processing hardware platform 3. The device integrates a bit error testing and channel simulation as a whole, and by utilizing a programmable process apparatus and / or the programmable equipment, the device also greatly simplifies the complexity and production difficulty of the hardware; meanwhile, the device also solves the problem that as the common bit error rate measuring devices lack channel simulation function, a channel simulator needs to be provided for testing bit error in the channel simulation environment, which leads the operation to be loaded down with trivial details and causes a waste of hardware resources. The invention also provides a method for fast configuring channel parameters. By arranging the parameters in a human-computer interface through the programmable processing equipment and by the virtue of a PCI bus transmission method, the simulation channels can be changed quickly according to the requirements of the user.

The invention provides a wireless network channel simulator which comprises a control background and a wireless network channel simulation module, wherein the control background is used for generating a wireless network channel script; and the wireless network channel simulation module is used for dynamically simulating an overhead wireless network channel and then simulating an actual wireless network environment under the control of the wireless network channel script. The invention also provides a system and a method for testing wireless network equipment. By using the wireless network channel simulator as well as system and method for testing the wireless network equipment provided by the invention, a system testing environment built in a laboratory can support PTM (point to multipoint) and MTP (multipoint to point) wireless network channel simulation capabilities, and the time for enabling base station systems or terminal products to appear on the market in batches are shortened.

The invention discloses a low-voltage orthogonal frequency division multiplexing (OFDM) carrier physical layer communication performance detecting system which is used for detecting emission performance indexes and receiving performance indexes of a low-voltage OFDM carrier physical layer. The detecting system comprises a signal isolation device, a standard carrier sending device, a carrier to be detected sending device, a carrier to be detected receiving device, a standard 50 omega impedance power network, a coupling circuit, two mixers, two adjustable attenuators, a white gaussian noise generator, a line impedance stabilizing network, a programmable logic controller (PLC) demodulation device, an alternating current power meter, a 220V alternating current power source, a signal generator, a network analyzer, a spectrum analyzer, a channel simulator, a signal analyzer and a computer. According to the technical characteristics of low-voltage power line carrier communication of an OFDM modulation mode, the detecting system is capable of conducting detailed test to the main performance indexes of the communication mode, the testing process is speedy, system conformability is high, system manufacturing cost is low, and space and labor cost are saved.

The invention discloses a wireless multipath fading channel simulating method and a channel simulator. The method comprises the following steps: measuring a channel between a transmitting antenna and a receiving antenna in actual environment, and measuring the frequency response of an actual measurement channel through frequency sweep; performing fourier inverse transform on the frequency response of the actual measurement channel so as to obtain the unit impulse response of the actual measurement channel; separating parameters in the unit impulse response of the actual measurement channel, and performing modeling so as to obtain a parameter model; storing the parameters of the model into a database; reading the parameters of the model, and generating the unit impulse response of a simulating channel; calculating a bit error ratio by utilizing Monte-Carlo simulation so as to complete channel simulation under the actual environment. The simulator comprises a channel measuring module, a module for extracting the unit impulse response of the actual measurement channel, a model building module, a model parameter extracting module and a simulating channel generating and verifying module. According to the wireless multipath fading channel simulating method and the channel simulator, disclosed by the invention, data can be measured in an actual manner, the model can be established, the bit error properties in different communication processes can be analyzed, and the channel obtained through simulation more conforms to the actual environment.

The invention discloses a space laser communication terminal level system testing method. Light beams are emitted from a tested terminal, pass through a telescope, a light-splitting optical path, a pointing error source simulator, a far-field receiving simulator, a collimation optical path and an atmospheric channel simulator in sequence, and are combined with light beams from a background light simulator through a beam-combining optical path. The combined light beams pass through a vibration-relative motion simulator, the light-splitting optical path and the telescope in sequence, and are received by an opposite-side tested terminal. Through adoption of the method, space laser communication terminal level system testing, including tracking and pointing characteristics (including tracking and pointing accuracy and tracking and pointing bandwidth), capturing characteristics (including capturing time and capturing probability), communication characteristics (including bit error rate and detection sensitivity) and the like are realized. The structure occupies a small space. Two communication terminals can perform terminal level system testing of multi-parameter direct alignment performance at a close range, and a plurality of external factors influencing space laser communication performance are simulated. The measuring accuracy is high.

The invention discloses a simulation communication system-based test system and a channel simulator. The performance test of frequency offset correction equipment under a super-speed mobile environment in a simulation communication system can be realized. The system comprises base station simulation equipment, the channel simulator, frequency offset correction equipment and a tester, wherein the base station simulation equipment is used for generating a primary signal and transmitting the primary signal to the channel simulator; the channel simulator is used for respectively determining level strength S1 and S2 of signals which are received by a mobile terminal which moves on a mobile track and transmitted by a first remote radio-head (RRH) module and a second RRH module, determining frequency f'1 and f'2 after doppler frequency shift, generating a first signal according to the S1, the f'1 and the primary signal, generating a second signal according to the S2, the f'2 and the primary signal, and transmitting the first signal and the second signal to the frequency offset correction equipment; the frequency offset correction equipment is used for respectively compensating the first signal and the second signal to obtain the compensated first signal and second signal; and the tester is used for determining the compensation performance of the frequency offset correction equipment.

The invention discloses a satellite channel high-dynamic time delay Doppler simulation system, relates to the technical field of satellite communication, and solves the problems of small simulation time delay and Doppler range and low change speed of an existing channel simulator. The system comprises an input unit, an FPGA control unit, an upper computer parameter control unit and an output unit.The FPGA control unit comprises a static time delay control unit, a dynamic time delay control unit and a Doppler frequency shift simulation unit; the FIFO function realized on the basis of the external DRAM memory structure can be subjected to large-range time delay; hardware adopts a PXI architecture, multi-channel expansion is realized, and a plurality of board cards are triggered in a daisy chain form. The fractional delay filter based on the least square method ensures accurate delay control in a large bandwidth range; Doppler and time delay continuous changes are supported; Doppler andtime delay joint synchronous control; a speed-adjustable control mode is updated based on the digital NCO parameters; and the satellite channel high-dynamic time delay Doppler simulation system can beexpanded into a multi-channel structure, and multiple channels can be accurately synchronized.

One embodiment illustrated herein includes a system for simulating communications in an environment. The system includes a postulated physical environment model, having modeled terrain and continuous changes over time. A channel parameter calculator is coupled to the postulated physical environment model, and configured to obtain samples from the postulated physical environment model, each sample comprising information about modeled terrain at a given time. The channel parameter calculator is further configured to, from the obtained samples, generate communication channel parameters, over time. A channel simulator is coupled to the channel parameter calculator. The channel simulator is configured to be coupled to signal source and to, using the communication channel parameters, apply the communication channel parameters to a communication signal from the signal source to simulate transmission of data through a simulated channel over time.

The invention discloses a high performance channel simulator radio frequency transceiver applied to 5G communication. The transceiver comprises a transmission link and a receiving link, in the transmission link, an intermediate frequency signal is signally transmitted out via a first intermediate frequency, an upper mixing module, a first automatic gain amplification control module, a single-poledouble-throw switch and a radio frequency filtering module in sequence; in the receiving link, a radio frequency signal is finally received via a radio frequency filtering module, the single-pole double-throw switch, a low noise amplifier, a second automatic gain control amplification module, a lower mixing module, a second intermediate frequency filtering module and a third automatic gain amplification control module in sequence; in addition, the transceiver also comprises a local oscillator module for providing local oscillator signals to the upper mixing module and the lower mixing module.According to the transceiver provided by the invention, the complexity of the channel simulator can be effectively reduced, the requirement on power of the signal channel in 5G research is reduced, the power consumption is lowered, and meanwhile the transceiver has the characteristics of large processing bandwidth, small area and good performance.

The invention discloses an aviation channel simulator and a simulation method, belonging to the modeling field of aviation channels. The aviation channel simulator comprises a channel simulation unit and a human-machine interaction module, wherein the channel simulation unit is used for simulating data with a ray tracing method to obtain the simulation result of the aviation channel after aviation data is received from one port of the simulation unit; then the traditional aviation channel is modeled by the simulation result to obtain a statistics channel model; after the other port receives a transmission signal, a real-time receiving signal is obtained with the ray tracing method so as to obtain the real-time response data of the channel; the statistics response curve of the traditional aviation channel is obtained from the transmission signal by the statistics channel model; and the human-machine interaction module is used for displaying the statistics response curve and the real-time response data of the channel. According to the aviation channel simulator and the simulation method, the aviation channel is efficiently, accurately and quickly modeled with low cost.

The present invention discloses a multi-channel meteor trail channel simulator, and relates to the transmission environment simulation equipment of meteor trail burst communication channel in the field of communication. The channel simulator comprises a digital control attenuator, a power distribution / synthesis device, a channel simulation unit, a power supply and other components. When in use, the channel simulator is connected in the meteor trail communication channel in series, to simulate the characteristics of the actual meteor trail channel, which comprise the appearance of random burst and the signal intensity of exponential decay; and the channel simulator can be used for simulation testing of various technical indicators of the meteor trail communication channel. The channel simulator also has the advantages of high degree of integration, simple circuit, small size, convenient use, stable and reliable performance, and so on, and is in particular suitable for the meteor trail channel simulator on the occasions of the joint testing of the system, the transmission threshold testing of the equipment, the capacity testing of the network protocol, and so on in the meteor trail communication system network under the condition of the laboratory.