CN101729299A - Channel simulation system - Google Patents
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- CN101729299A CN101729299A CN200810167949A CN200810167949A CN101729299A CN 101729299 A CN101729299 A CN 101729299A CN 200810167949 A CN200810167949 A CN 200810167949A CN 200810167949 A CN200810167949 A CN 200810167949A CN 101729299 A CN101729299 A CN 101729299A
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Abstract
The invention relates to a channel simulation system, which solves the problem of coverage failure of the traditional channel simulator. The system can cover the frequency channel which is adopted by the conventional wireless local area network and has a test frequency channel which at least reaches 60 GHz according to probability of the frequency channel used in future. The system has a standard template of simulation parameters in a short-distance wireless transmission environment. The system can automatically set all the parameters of channel fading according to the parameters such as the building size input by an operator, the position of equipment to be tested and the like.
Description
Technical field
The present invention relates to a kind of communication technology, relate in particular to a kind of channel simulation system.
Background technology
In mobile communication system, wireless propagation environment is an important research project.Usually, we not only need to mobile communication equipment carry out conventional radio-frequency (RF) index such as power output, take the test of static indexs such as frequency spectrum, the receiver error rate, also will weigh under the condition of these equipment after having simulated real wireless propagation environment, whether the index of system can also reach the requirement of reservation.In main mobile communication standard such as GSM, CDMA, W-CDMA, CDMA2000, all to fade condition many test events of having given a definition.And the wireless channel simulation device becomes the indispensable instrument of finishing these project testings as important instrument that can the artificial antenna communication environments.
At present, the wireless channel simulation device has only external instrument manufacturer production, and major vendor is SPIRENT, NOISECOM etc.Wherein, TAS4500 is to use one of model the most widely.It can analog wireless channel fading characteristic, produce time delay, decay, dissemination channel characteristics such as phase shift, functions such as simulation rapid fading slow fading.In the test of mobile communication, mode that need be specific usually to system definition undetermined, because the applied environment of different mobile communication system, the frequency range that takies, conditions such as user's translational speed are different.The decline template that this simulator has had has GSM, CDMA etc.
But existing TAS4500 frequency range can only arrive 3GHz, and existing some wireless system such as WLAN (wireless local area network) have been used the frequency range of 5.8GHz, therefore need carry out the simulation of wireless channel on this frequency range.And the existing decline template of TAS4500 has only systems such as GSM, CDMA at present, and for the applied short-distance wireless communication environments of other system, particularly WLAN (wireless local area network), does not have corresponding test template.
Summary of the invention
Goal of the invention of the present invention provides a kind of channel simulation system.Solve the problem that the conventional channel analog instrument can't cover the use frequency range of existing WLAN (wireless local area network).This system can cover the use frequency range of existing WLAN (wireless local area network), and the test frequency range reaches 6GHz at least, has considered possible from now on use frequency range.This system possesses the standard form of short-distance wireless communication environments analog parameter.This system can be according to the building size of operator's input, and parameters such as equipment under test position are provided with the parameters of channel fading automatically.
The invention discloses a kind of channel simulation system, comprising:
The frequency conversion system module, high-precision signal source, mixing and filtering module and control section that it comprises as local oscillator are used for downconverting the signal to less characteristic frequency when the radiofrequency signal of input surpasses 3GHz, after finishing the decline simulation, again output signal is reduced to the rf frequency of input;
Decline analogue system module, it comprises that frequency range is that channel simulator, the WLAN (wireless local area network) interface of 3GHz forms part, computer, control card, bus, is used for the setting of parameter and the realization emulation to channel that declines of wherein described channel simulator;
Described WLAN (wireless local area network) interface forms part and is used to form the various WLAN (wireless local area network) bound of parameter faces of input.
Described mixing and filtering module comprises:
Power splitter, a plurality of frequency mixers, filter.
The maximum frequency range of the input signal of described channel simulation system is more than or equal to 6GHz.
Described characteristic frequency is set at 1GHz.
Description of drawings
Fig. 1 shows the structure chart of the channel simulation system of the embodiment of the invention;
Fig. 2 shows the concrete structure figure of mixing and filtering module;
Fig. 3 is a mixing and filtering module front panel joint schematic diagram;
Fig. 4 is the down-conversion schematic diagram;
Fig. 5 is up-conversion and filtering schematic diagram;
Fig. 6 shows the program structure frame diagram of the embodiment of the invention;
Fig. 7 shows the input control page;
Fig. 8 shows time delay the page is set;
Fig. 9 shows modulation system the page is set;
Figure 10 shows relative loss factor the page is set;
Figure 11 shows the Log-Normal parameter page is set;
Figure 12 shows the output control setting page;
Figure 13 A shows template the page is set;
Figure 13 B shows CHANNEL analog module structure chart;
Figure 14 shows reflection the page is set;
Figure 15 shows verifying test system figure.
Figure 16 is Rayleigh decline analog result (frequency spectrum) figure;
Figure 17 is Rayleigh decline analog result (time domain) figure;
Figure 18 is Racian decline analog result figure;
Figure 19 is Frequency Shift analog result figure;
Figure 20 is Log-Normal Shadowing analog result figure.
Embodiment
Understand and realization the present invention the existing embodiments of the invention of describing in conjunction with the accompanying drawings for the ease of persons skilled in the art.
The channel simulation system of the embodiment of the invention is made up of frequency conversion system module and decline analogue system module two big modules.As shown in Figure 1.
The frequency conversion system module mainly is made up of high-precision signal source, mixing and filtering module and control section as local oscillator.The frequency conversion system module functions is when the radiofrequency signal of input surpasses 3GHz, downconverts the signal to lower frequency range, after finishing the decline simulation, output signal is reduced to the rf frequency of input again.In embodiments of the present invention, our signal sets after down-conversion is 1GHz.
The operation principle of frequency conversion system module is, frequency by Control Software control local oscillation signal, WLAN signal outside the wireless channel simulation device TAS4500 operating frequency range frequency mixing module of making a gift to someone is carried out down-conversion (as shown in Figure 4), signal is changed within the scope that TAS4500 can handle, and then the signal after the frequency conversion is sent into TAS4500 handle (TAS4500 can be controlled by PC equally); Signal after TAS4500 handles is sent into the mixing and filtering module again and is carried out up-conversion and filtering (as shown in Figure 5), and the signal of RF OUTPUT port output just is in identical frequency range with the signal of RF INPUT port input so in the drawings.The concrete structure of mixing and filtering module as shown in Figure 2.
Decline analogue system module is made up of, in embodiments of the present invention wireless channel simulation module, Control Software, computer, GPIB control card, bus, and functions such as the wireless channel simulation module and being provided with of parameter that decline are finished by Control Software.Computer, GPIB control card, gpib bus are auxiliary equipment.
The structure of program is made up of two parts: interface (GUI)+dynamic link library (DLL).The function of graphic user interface is to accept input, passes to corresponding dynamic chained library file according to the information of importing, and relevant instrument is controlled, and a result who handles is shown as required.Use independently that the benefit of GUI and dynamic link library file is that whole system is decomposed into a plurality of independently modules, can carry out independent debugging, help the stability of system GUI and library file; Simultaneously, the dynamic link library file that debugging is passed through can be different process transfers, and need not to increase extra resource overhead, can significantly reduce taking of system resource.Simultaneously, can upgrade to the storehouse separately, as long as the interface statement does not change, application program does not need to change or recompilate the storehouse that just can use version updating.
Computer instructs by the IEEE-488.2SCPI that inner GPIB card sends standard, realizes the control to corresponding instrument.
The software configuration of system as shown in Figure 6, application graphical user interface (GUI) is positioned at the superiors, its function is the reciprocation of realization information; The correct configuration information of on the interface, importing, be delivered to the dynamic link library file of more following one deck after treatment by the interface between GUI and the DLL, dynamic link library file passes to the data that receive and control command 488.2 drivers of lower floor again, then corresponding SCPI instruction just can send to corresponding instrument with gpib bus between the instrument by computer, instrument is controlled and is provided with, also return necessary meter status information simultaneously.
Briefly bright to the various piece of GUI below:
Fig. 7 can be provided with carrier frequency, local oscillator pattern, local frequency, input reference level for the input control page, can also independently select every paths simultaneously.
Fig. 8 is provided with the page for time delay, and the value in relative time delay of each path can independently be set.
Fig. 9 is provided with the page for modulation system, and the parameters such as modulation type, Racian k factor, Doppler frequency displacement, LOS DOPP, speed, the angle of arrival, phase place and Rayleigh frequency displacement of each path can independently be set.
Figure 10 is provided with the page for relative loss factor, and the relative loss factor of every paths can independently be set.
Figure 11 is provided with the page for the Log-Normal parameter, and the parameters such as Log-Normal state, deviation and rates of every paths can be set.
Figure 12 can be provided with radio frequency output attenuatoin value for the output control setting page.
Figure 13 A is that template is provided with the page, can be written into JTC ' 94 indoor decline models, exponential damping Rayleigh fading model and HIPERLAN/2 decline model.The PATH number of the CHANNEL that these template models have has surpassed 6, for this situation, we use the method for Figure 13 B, and two CHANNEL of TAS4500 are simulated a CHANNEL altogether, maximum like this 12 PATH that can simulate a CHANNEL.
Figure 14 is provided with the page for reflection, in this page, can import the parameters such as coordinate values of the size numerical value in a room and transmitter, receiver, and carry out simulation calculation according to these numerical value, obtain the reflection angle of primary event and secondary reflection and the important parameters such as coordinate of pip, and then go out results such as loss, time delay and phase place by these calculation of parameter again.
By the control of above-mentioned menu, the tester can finish all parameter settings.
In order to verify whether the every function of channel simulation system of the present invention has reached re-set target.Plan from following two aspects to the checking that experimentizes of the function of channel simulation system of the present invention:
Whether the wireless channel simulation device is provided with correctly with each parameter setting values of WLAN decline masterplate in the standard masterplate comparison software; Channel simulator function in the software is verified.
At first, prepare a laboratory, ad-hoc location in laboratory is placed transmitting antenna and reception antenna, is used for analog transmissions and receiving equipment.Use the channel response after network analyzer is measured transmitting antenna arrival reception antenna, parameters such as decay and time delay.Measurement system diagram as shown in figure 15.Then, the size in input room in software, the position of antenna is accepted in emission, and parameters such as the position of barrier draw the channel simulator parameter that software is simulated, and compare with the measurement result of front.If both result who obtains meets preferably, verified that then the software simulation function has reached the set goal and index.
The verification msg of hardware index is as follows.
System's local frequency accuracy:
| Indicating value (MHz) | Measured value (MHz) |
| ??940.000 | ??940.000027 |
| ??1040.000 | ??1040.000031 |
| ??1940.000 | ??1940.000039 |
| ??2040.000 | ??2040.000041 |
| ??2140.000 | ??2140.000043 |
| ??2240.000 | ??2240.000047 |
| ??2340.000 | ??2340.000051 |
| ??2440.000 | ??2440.000054 |
| ??2540.000 | ??2540.000056 |
| ??2640.000 | ??2640.000059 |
| ??2740.000 | ??2740.000061 |
| ??2860.000 | ??2860.000067 |
| ??3000.000 | ??3000.000072 |
| ??4000.000 | ??4000.000081 |
| ??5000.000 | ??5000.000090 |
| ??6000.000 | ??6000.000095 |
| ??7000.000 | ??7000.000097 |
| ??8000.000 | ??8000.000099 |
The expanded uncertainty of measurement result (k=2): 5.8 * 10
-9
| Indicating value (dB) | Measured value (dB) | Expanded uncertainty (k=2) |
| ??900MHz | ??1.8GHz | ??(dB) | |
| ??10.0 | ??9.97 | ??9.98 | ??0.24 |
| ??20.0 | ??19.98 | ??20.02 | ??0.26 |
| ??30.0 | ??30.07 | ??30.05 | ??0.26 |
| ??40.0 | ??40.02 | ??40.05 | ??0.26 |
| ??50.0 | ??49.82 | ??49.79 | ??0.32 |
Channel paths BYPASS functional check:
The bypass function of conclusion: Channel 1 and Channel 2 is normal.
Rayleigh declines analog result (frequency spectrum) as shown in figure 16, and reference record is as follows:
Input signal: 5.8GHz level :-10dBm modulation: do not have
TAS4500 is provided with: Rayleigh; Velocity:100km/hr
The expanded uncertainty of measurement result (k=2): 1.94Hz
Rayleigh declines analog result (time domain) as shown in figure 17, and reference record is as follows:
Input signal: 5.8GHz level :-10dBm modulation: do not have
TAS4500 is provided with: Rayleigh; Velocity:100km/hr
Racian declines analog result as shown in figure 18, and reference record is as follows:
Input signal: 5.8GHz level :-10dBm modulation: do not have
TAS4500 is provided with: GSM_Racian; Velocity:100km/hr
Frequency Shift analog result as shown in figure 19, reference record is as follows:
Input signal: 5.8GHz level :-10dBm modulation: do not have
TAS4500 is provided with: Frequency Shift; Doppler:241.7Hz
The expanded uncertainty of measurement result (k=2): 1.94Hz
Log-Normal Shadowing analog result as shown in figure 20, reference record is as follows:
Input signal: 5.8GHz level :-10dBm modulation: do not have
TAS4500 is provided with: LOG NORMAL; LOG NORMAL STD:8dB; LOG NORMAL RATE:0.5Hz
The checking record of software function is as follows.
WLAN masterplate parameter call result:
Conclusion: template parameter calls the result and is provided with consistent with standard masterplate parameter.
The channel simulator functional verification:
Simulated environment 1: office environment 1
Size: 10m (length) * 6.2m (wide) * 3.2m (height)
Transmitter site: 2m (length) * 2.5m (wide) * 1.2m (height)
Receiver location: 9m (length) * 2.5m (wide) * 1.2m (height)
Transmitter antenna gain: 5dBi
Receiver antenna gain: 5dBi
Cable and adapter loss: 3.5dB
Test frequency: 5.8GHz
Transmitter transmitting power: 0dBm
| Test event | Software simulation result of calculation | The network analyzer measured result | Deviation |
| Path loss | ??64.9dB | ??65.2dB | ??0.3dB |
| Time delay | ??23.3ns | ??23.5ns | ??0.2ns |
Simulated environment 2: office environment 2
Size: 15m (length) * 8m (wide) * 3.0m (height)
Transmitter site: 2m (length) * 2.5m (wide) * 1.2m (height)
Receiver location: 13m (length) * 5.5m (wide) * 1.0m (height)
Transmitter antenna gain: 5dBi
Receiver antenna gain: 5dBi
Cable and adapter loss: 3.5dB
Test frequency: 5.8GHz
Transmitter transmitting power: 0dBm
| Test event | Software simulation result of calculation | The network analyzer measured result | Deviation |
| Path loss | ??69.1dB | ??68.9dB | ??-0.2dB |
| Time delay | ??38.0ns | ??37.7ns | ??-0.3ns |
Simulated environment 3: office environment 3
Size: 12m (length) * 5m (wide) * 2.8m (height)
Transmitter site: 1.5m (length) * 2.5m (wide) * 1.5m (height)
Receiver location: 10.2m (length) * 1.5m (wide) * 1.3m (height)
Transmitter antenna gain: 5dBi
Receiver antenna gain: 5dBi
Cable and adapter loss: 3.5dB
Test frequency: 5.8GHz
Transmitter transmitting power: 0dBm
| Test event | Software simulation result of calculation | The network analyzer measured result | Deviation |
| Path loss | ??66.8dB | ??66.4dB | ??-0.4dB |
| Time delay | ??29.2ns | ??29.6ns | ??0.4ns |
Simulated environment 4: office environment 4
Size: 12m (length) * 5m (wide) * 2.8m (height)
Transmitter site: 1.5m (length) * 2.5m (wide) * 1.5m (height)
Receiver location: 10.2m (length) * 1.5m (wide) * 1.3m (height)
Transmitter antenna gain: 5dBi
Receiver antenna gain: 5dBi
Cable and adapter loss: 3.5dB
Test frequency: 2.4GHz
Transmitter transmitting power: 0dBm
| Test event | Software simulation result of calculation | The network analyzer measured result | Deviation |
| Path loss | ??58.8dB | ??58.5dB | ??-0.3dB |
| Test event | Software simulation result of calculation | The network analyzer measured result | Deviation |
| Time delay | ??29.2ns | ??29.5ns | ??0.3ns |
As seen, every function of channel simulation system of the present invention, index have have all met or exceeded re-set target.
Though described the present invention by embodiment, those of ordinary skills know, without departing from the spirit and substance in the present invention, just can make the present invention that many distortion and variation are arranged, and scope of the present invention is limited to the appended claims.
Claims (4)
1. a channel simulation system is characterized in that, comprising:
The frequency conversion system module, high-precision signal source, mixing and filtering module and control section that it comprises as local oscillator are used for downconverting the signal to less characteristic frequency when the radiofrequency signal of input surpasses 3GHz, after finishing the decline simulation, again output signal is reduced to the rf frequency of input;
Decline analogue system module, it comprises that frequency range is that channel simulator, the WLAN (wireless local area network) interface of 3GHz forms part, computer, control card, bus, is used for the setting of parameter and the realization emulation to channel that declines of wherein described channel simulator;
Described WLAN (wireless local area network) interface forms part and is used to form the various WLAN (wireless local area network) bound of parameter faces of input.
2. channel simulation system according to claim 1 is characterized in that, described mixing and filtering module comprises: power splitter, a plurality of frequency mixers, filter.
3. channel simulation system according to claim 1 is characterized in that, the maximum frequency range of the input signal of described channel simulation system is more than or equal to 6GHz.
4. channel simulation system according to claim 1 is characterized in that described characteristic frequency is set at 1GHz.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107484197A (en) * | 2017-05-23 | 2017-12-15 | 南京航空航天大学 | The wireless fading channel analogue means and method of any Doppler power spectra |
| CN107994965A (en) * | 2018-01-30 | 2018-05-04 | 合肥工业大学 | A kind of lognormal channel models verify system |
| CN108259098A (en) * | 2018-01-24 | 2018-07-06 | 合肥工业大学 | A kind of verification system of Rayleigh-Butterworth fading channel |
| CN112699525A (en) * | 2020-12-02 | 2021-04-23 | 北京邮电大学 | Calculation method and equipment of Rayleigh channel simulator |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100386985C (en) * | 2005-03-04 | 2008-05-07 | 华为技术有限公司 | Channel simulation device and method capable of expanding channel simulation bound |
| CN101079675A (en) * | 2007-06-29 | 2007-11-28 | 中兴通讯股份有限公司 | A method, device and system for testing the multi-path attenuation |
-
2008
- 2008-10-20 CN CN2008101679495A patent/CN101729299B/en active Active
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107484197A (en) * | 2017-05-23 | 2017-12-15 | 南京航空航天大学 | The wireless fading channel analogue means and method of any Doppler power spectra |
| CN107484197B (en) * | 2017-05-23 | 2020-10-20 | 南京航空航天大学 | Wireless fading channel simulation device and method of any Doppler power spectrum |
| CN108259098A (en) * | 2018-01-24 | 2018-07-06 | 合肥工业大学 | A kind of verification system of Rayleigh-Butterworth fading channel |
| CN107994965A (en) * | 2018-01-30 | 2018-05-04 | 合肥工业大学 | A kind of lognormal channel models verify system |
| CN107994965B (en) * | 2018-01-30 | 2020-08-28 | 合肥工业大学 | Lognormal channel model verification system |
| CN112699525A (en) * | 2020-12-02 | 2021-04-23 | 北京邮电大学 | Calculation method and equipment of Rayleigh channel simulator |
| CN112699525B (en) * | 2020-12-02 | 2023-10-03 | 北京邮电大学 | Calculation method and equipment of Rayleigh channel simulator |
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| CN101729299B (en) | 2012-01-25 |
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