CN102082750A - Method and device for eliminating direct current bias - Google Patents
Method and device for eliminating direct current bias Download PDFInfo
- Publication number
- CN102082750A CN102082750A CN2009102000128A CN200910200012A CN102082750A CN 102082750 A CN102082750 A CN 102082750A CN 2009102000128 A CN2009102000128 A CN 2009102000128A CN 200910200012 A CN200910200012 A CN 200910200012A CN 102082750 A CN102082750 A CN 102082750A
- Authority
- CN
- China
- Prior art keywords
- data
- predetermined number
- intermediate value
- direct current
- described predetermined
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Noise Elimination (AREA)
Abstract
The invention relates to the technical field of radio frequency receiving, and discloses a method and device for eliminating direct current bias. The method comprises the following steps: acquiring a preset amount of data received on a digital base band; calculating the median of the preset amount of data, and adopting the median as the current direct current bias; and subtracting the direct current bias from the data received on the digital base band as the data actually received on the digital base band. By adopting the method and device provided by the invention, direct current bias in radio frequency receiving can be effectively eliminated, the radio frequency receiving performance can be improved, and the burst interference which can not be overcome by an averaging method can be inhibited.
Description
Technical field
The present invention relates to the radio frequency reception technique, be specifically related to a kind of method and device of cancellation of DC offset.
Background technology
In present radio-frequency transmitter, zero-if architecture is used more and more widely.So-called zero intermediate frequency reciver is meant that radiofrequency signal directly becomes the receiver structure that centre frequency is zero baseband signal by mixing, and this structure chip integration height needs external device few, and monolithic is integrated easily, has low, the low in energy consumption advantage of cost.But zero-if architecture is also introduced some other problemses, and such as direct current offset, local-oscillator leakage, the interference of low noise amplifier even-order harmonic, flicker noise etc., a wherein most important problem is a direct current offset.
Direct current offset mainly is that the self-mixing owing to local oscillation signal produces in downconversion process.Because the local oscillator mouth and the isolation performance between the radio frequency mouth of frequency converter can not be desirable, local oscillation signal can be from the radio frequency mouth output of frequency converter, leak into antenna by high-frequency amplifier again, the local oscillation signal that leaks is got back to high-frequency amplifier from antenna, enter the radio frequency mouth of low-converter, the local oscillation signal that it and local oscillator mouth enter is through mixing, and difference frequency is a zero frequency, is direct current offset.In addition, not matching of the even distortion of signal and baseband circuit also can produce direct current offset.All these direct current offsets are superimposed upon on the baseband signal, and these direct current offsets often noise than radio-frequency front-end are also big, this not only can make the signal to noise ratio variation, and these big direct current offsets also may make the amplifiers at different levels behind the frequency mixer saturated, can't amplify useful signal.If direct current offset enters digital baseband, can produce further influence to the performance of whole receiving system.Therefore from the application point of chip, must consider direct current offset is eliminated that the direct current offset in the data how cancellation receiver receives also just becomes problem demanding prompt solution.
A solution of prior art is: utilize following formula to calculate the average of the data that receive:
Wherein, x (i) is the data that receive at digital baseband, and N is the number that is used to estimate the data of direct current, and DC is direct current offset;
To calculate average, then, from the data that receive, deduct the direct current offset that calculates again, so eliminate as current direct current offset.
Yet when averaging in the reality, because the restriction of statistics length, the average that calculates can not reflect the size of dc offset exactly.Therefore, above-mentioned use averaging method is carried out the direct current offset elimination, however can make data introduce certain distortion, thus the performance of system is affected, measure as SNR and forbidden degradation under the systematic function.Particularly for the situation that bursty interference is arranged in the signal, the signal waveform that has burst as shown in Figure 1, when bursty interference is arranged,, have a strong impact on the performance of system if the employing averaging method is carried out the elimination meeting of direct current offset because the influence of bursty interference causes the estimation of DC component inaccurate.
Summary of the invention
The embodiment of the invention provides a kind of method and device of cancellation of DC offset, eliminates the direct current offset in the radio frequency reception effectively, improves the radio frequency receptivity, and can suppress the bursty interference that averaging method can't overcome.
For this reason, the embodiment of the invention provides following technical scheme:
A kind of method of cancellation of DC offset comprises:
Obtain the data of the predetermined number that receives at digital baseband;
Calculate the intermediate value of the data of described predetermined number, and with described intermediate value as current direct current offset;
In the data that digital baseband receives, deduct the data of described direct current offset as the digital baseband actual reception.
Preferably, the intermediate value of the data of the described predetermined number of described calculating comprises:
Calculate the average M of the data of described predetermined number, described predetermined number is N;
Determine that numerical value is less than the number K of described average M in the described N data;
If
Then will be less than the intermediate value of the maximum in K the data of average M as the data of described predetermined number;
Otherwise, from a described N data, take out partial data according to the value of K and sort, with the intermediate value of the sequence after the ordering as the intermediate value of the data of described predetermined number.
Preferably, partial data sorted and comprises during described value according to K was got from a described N data:
If
Then take out K data, according to descending rank order less than M;
If
Then take out N-K data, according to ascending rank order greater than M.
Alternatively, the intermediate value of the data of the described predetermined number of described calculating comprises:
To the data of described predetermined number according to ascending or descending rank order, with the intermediate value of the sequence after the ordering intermediate value as the data of described predetermined number.
A kind of device of cancellation of DC offset comprises:
Acquiring unit is used to obtain the data in the predetermined number of digital baseband reception;
Computing unit calculates the intermediate value of the data of described predetermined number, and with described intermediate value as current direct current offset;
Eliminate the unit, be used for deducting the data of described direct current offset as the digital baseband actual reception in the data that digital baseband receives.
Preferably, described computing unit comprises:
The mean value computation subelement is used to calculate the average M of the data of described predetermined number, and described predetermined number is N;
Quantity is determined subelement, is used for determining the number K of described N data numerical value less than described average M;
Subelement relatively, be used for comparison K with
Size;
First determines subelement, is used for
The time, will be less than the intermediate value of the maximum in K the data of average M as the data of described predetermined number;
Second determines subelement, is used for
The time, from a described N data, take out partial data according to the value of K and sort, with the intermediate value of the sequence after the ordering as the intermediate value of the data of described predetermined number.
Preferably, described second determines that subelement comprises:
The ordering subelement is used for
Taking-up is less than K the data of M, according to descending rank order;
Taking-up is greater than N-K the data of M, according to ascending rank order;
Intermediate value is chosen subelement, is used for intermediate value with the sequence after the ordering as the intermediate value of the data of described predetermined number.
Alternatively, described computing unit specifically is used for data to described predetermined number according to ascending or descending rank order, with the intermediate value of the sequence after the ordering intermediate value as the data of described predetermined number.
The method of embodiment of the invention cancellation of DC offset and device are by obtaining the data of the predetermined number that receives at digital baseband; Calculate the intermediate value of the data of described predetermined number, and with described intermediate value as current direct current offset; In the data that digital baseband receives, deduct the data of described direct current offset as the digital baseband actual reception.Can eliminate the direct current offset in the radio frequency reception effectively, improve the radio frequency receptivity, and can suppress the bursty interference that averaging method can't overcome.
Description of drawings
Fig. 1 is the schematic diagram that has the signal waveform of burst in the prior art;
Fig. 2 is not having under the situation of direct current offset, is subjected to the CDF simulation result schematic diagram of the data of white Gaussian noise interference;
Fig. 3 is not having under the situation of direct current offset, is subjected to the PDF simulation result schematic diagram of the data of white Gaussian noise interference;
Fig. 4 is the flow chart of the method for embodiment of the invention cancellation of DC offset;
Fig. 5 is a kind of specific implementation flow chart of the method for embodiment of the invention cancellation of DC offset;
Fig. 6 is a radio-frequency transmitter rear end snr measurement curve;
Fig. 7 is the Block Error Rate of the fixed reference channel test of HSDPA;
Fig. 8 is the structural representation of the device of embodiment of the invention cancellation of DC offset;
Fig. 9 is a kind of preferred structure schematic diagram of computing unit in the embodiment of the invention.
Embodiment
In order to make those skilled in the art person understand the scheme of the embodiment of the invention better, the embodiment of the invention is described in further detail below in conjunction with drawings and embodiments.
At utilizing the averaging method cancellation of DC offset to have in signal under the situation of bursty interference in the prior art, the estimation of DC component is inaccurate, and then influences the problem of the performance of system, and the embodiment of the invention adopts median method that direct current offset is eliminated.
By probability theory as can be known, as long as the data length long enough of statistics is not having under the situation of direct current offset, the distribution of data on 0 value both sides that influenced by white Gaussian noise is equiprobable.
As shown in Figure 2, be not have under the situation of direct current offset, be subjected to the simulation result schematic diagram of the CDF (Cumulative Distribution Function, cumulative distribution function) of the data that white Gaussian noise disturbs.Fig. 3 is not having under the situation of direct current offset, is subjected to the simulation result schematic diagram of the PDF (ProbabilityDistribution Function, probability-distribution function) of the data that white Gaussian noise disturbs.
Wherein, the real part of Real representative data, the imaginary part of Imag representative data.As seen from the figure, the data on 0 value both sides are that strict equiprobability distributes.
Can prove that by above theory analysis and simulation result as long as the data length long enough of statistics, the data on 0 value both sides are that strict equiprobability distributes.In like manner, can release, when having direct current offset DC, data also are to wait general the distribution on the DC both sides.According to this good distribution character, can think that intermediate value can reflect the size of direct current offset comparatively exactly, the elimination of adopting median method to carry out direct current offset is feasible.
For this reason, the method for embodiment of the invention cancellation of DC offset is by obtaining the data of the predetermined number that receives at digital baseband; Calculate the intermediate value of the data of described predetermined number, and with described intermediate value as current direct current offset; In the data that digital baseband receives, deduct the data of described direct current offset as the digital baseband actual reception.
As shown in Figure 4, be the flow chart of the method for embodiment of the invention cancellation of DC offset, may further comprise the steps:
Step 401 is obtained the data in the predetermined number of digital baseband reception;
Step 402 is calculated the intermediate value of the data of described predetermined number, and with described intermediate value as current direct current offset;
Step 403 deducts the data of described direct current offset as the digital baseband actual reception in the data that digital baseband receives.
Median method can be eliminated the direct current offset in the radio frequency reception effectively for realizing more simple averaging method, improve the radio frequency receptivity, and can suppress the bursty interference that averaging method can't overcome.And for adopting filter or special direct current to eliminate for the circuit, median method has the low advantage of implementation complexity.It is that a kind of performance is more excellent that the median method direct current is eliminated, and the method that implementation complexity is low is convenient to use in practice very much.Especially when having the situation of spread spectrum and many code channels, because spread spectrum can be eliminated the DC component (spreading code is positive and negative replacing) of extra introducing, and under many code channels situation, the data volume that participates in median calculation increases, thereby the intermediate value that obtains is more accurate.
Need to prove, when in above-mentioned steps 302, calculating the intermediate value of data of described predetermined number, can adopt the mode that all data are sorted, particularly, to the data of described predetermined number according to ascending or descending rank order, with the intermediate value of the sequence after the ordering intermediate value as the data of described predetermined number.
Certainly, in order further to reduce amount of calculation, the embodiment of the invention also provides a kind of preferred method for simplifying.
As shown in Figure 5, be a kind of specific implementation flow chart of the method for embodiment of the invention cancellation of DC offset, may further comprise the steps:
Step 501 is obtained N the data x (i) that receives at digital baseband;
Step 502 is calculated the average M of described N data x (i);
Step 503 determines that numerical value is less than the number K of M in N the data;
Step 504 judges whether K equals
If then execution in step 505; Otherwise execution in step 506;
Step 505 is taken out the maximum less than K the data of M, and with this maximum as current direct current offset; Then, execution in step 509;
Step 507 is taken out K data less than M, according to descending rank order, with the intermediate value of the sequence after sorting as current direct current offset, promptly
Then, execution in step 509;
Step 508 is taken out N-K data greater than M, according to ascending rank order, with the intermediate value of the sequence after sorting as current direct current offset, promptly
Step 509 deducts the data of described direct current offset as the digital baseband actual reception in the data that digital baseband receives.
Certainly, the embodiment of the invention also is not limited only to aforesaid way when calculating intermediate value, also can adopt the mode of other calculating intermediate value.
As seen, the method for this embodiment cancellation of DC offset not only can be eliminated the direct current offset in the radio frequency reception effectively, improves the radio frequency receptivity, and can suppress the bursty interference that averaging method can't overcome; And reduced amount of calculation.
Further, the result has also confirmed the improvement of the embodiment of the invention to the radio frequency receptivity respectively from measurement accuracy and systematic function two aspects by experiment.
As shown in Figure 6, be that radio-frequency transmitter rear end SNR (Signal to Noise Ratio, signal to noise ratio) measures curve.
Wherein, Middle value, i.e. curve 61 expressions utilize the method for the embodiment of the invention to carry out the curve that direct current offset is eliminated; Mean value, i.e. the curve of curve 62 expression averaging method direct current offsets eliminations; NoDCO, i.e. the curve that direct current offset is eliminated is not done in curve 60 expressions.
As shown in Figure 7, be the BLER (Block Error Ratio, Block Error Rate) that tests at the FRC (Fixed Reference Channel, fixed reference channel) of HSDPA (High Speed Downlink Packet Access, high speed downlink packet inserts).
Abscissa Ior among the figure (The received power spectral density)/Ioc (The power spectraldensity) is the size of signal to noise ratio, and wherein Ior and Ioc are respectively UE receiving end signal power spectral density and noise (comprising presence of intercell interference and other noises) power spectral density.
As seen from Figure 7, use the scheme of the embodiment of the invention, eliminate with the averaging method direct current offset and compare, when high s/n ratio, receptivity can promote about 0.5dB.Performance is consistent when adopting the median method direct current offset to eliminate almost with no direct current offset.
As seen, utilize the scheme of the embodiment of the invention can improve the accuracy that the radio-frequency transmitter rear end is measured, improve receptivity, the receptivity during especially than high s/n ratio.
One of ordinary skill in the art will appreciate that all or part of step that realizes in the foregoing description method is to instruct relevant hardware to finish by program, described program can be stored in the computer read/write memory medium, described storage medium, as: ROM/RAM, magnetic disc, CD etc.
Correspondingly, the embodiment of the invention also provides a kind of device of cancellation of DC offset, as shown in Figure 8, is a kind of structural representation of this device.
In this embodiment, described device comprises:
Acquiring unit 801 is used to obtain the data in the predetermined number of digital baseband reception;
Computing unit 802 calculates the intermediate value of the data of described predetermined number, and with described intermediate value as current direct current offset;
Eliminate unit 803, be used for deducting the data of described direct current offset as the digital baseband actual reception in the data that digital baseband receives.
In embodiments of the present invention, described computing unit 802 can adopt the mode that all data are sorted to calculate the intermediate value of the data of described predetermined number, particularly, to the data of described predetermined number according to ascending or descending rank order, with the intermediate value of the sequence after the ordering intermediate value as the data of described predetermined number.
Certainly, in order further to reduce amount of calculation, the embodiment of the invention also provides a kind of preferred embodiment to described computing unit 802.
As shown in Figure 9, be a kind of preferred structure schematic diagram of computing unit in the embodiment of the invention.
In this embodiment, described computing unit comprises:
Mean value computation subelement 901 is used to calculate the average M of the data of described predetermined number, and described predetermined number is N;
Quantity is determined subelement 902, is used for determining the number K of described N data numerical value less than described average M;
Subelement 903 relatively, be used for comparison K with
Size;
First determines subelement 904, is used for
The time, will be less than the intermediate value of the maximum in K the data of average M as the data of described predetermined number;
Second determines subelement 905, is used for
The time, according to the value of K from a described N data
Take out partial data and sort, with the intermediate value of the sequence after the ordering intermediate value as the data of described predetermined number.
Described second determines that subelement 905 comprises: ordering subelement and intermediate value are chosen subelement.Wherein, described ordering subelement is used for
Taking-up is less than K the data of M, according to descending rank order;
Taking-up is greater than N-K the data of M, according to ascending rank order; Described intermediate value is chosen subelement, is used for intermediate value with the sequence after the ordering as the intermediate value of the data of described predetermined number.
The device of embodiment of the invention cancellation of DC offset can be eliminated the direct current offset in the radio frequency reception effectively, improves the radio frequency receptivity, and can suppress the bursty interference that averaging method can't overcome.
More than the embodiment of the invention is described in detail, used embodiment herein the present invention set forth, the explanation of above embodiment just is used for help understanding method and apparatus of the present invention; Simultaneously, for one of ordinary skill in the art, according to thought of the present invention, the part that all can change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention.
Claims (8)
1. the method for a cancellation of DC offset is characterized in that, comprising:
Obtain the data of the predetermined number that receives at digital baseband;
Calculate the intermediate value of the data of described predetermined number, and with described intermediate value as current direct current offset;
In the data that digital baseband receives, deduct the data of described direct current offset as the digital baseband actual reception.
2. method according to claim 1 is characterized in that, the intermediate value of the data of the described predetermined number of described calculating comprises:
Calculate the average M of the data of described predetermined number, described predetermined number is N;
Determine that numerical value is less than the number K of described average M in the described N data;
If
Then will be less than the intermediate value of the maximum in K the data of average M as the data of described predetermined number;
Otherwise, from a described N data, take out partial data according to the value of K and sort, with the intermediate value of the sequence after the ordering as the intermediate value of the data of described predetermined number.
3. method according to claim 2 is characterized in that, partial data sorted and comprises during described value according to K was got from a described N data:
If
Then take out K data, according to descending rank order less than M;
If
Then take out N-K data, according to ascending rank order greater than M.
4. method according to claim 1 is characterized in that, the intermediate value of the data of the described predetermined number of described calculating comprises:
To the data of described predetermined number according to ascending or descending rank order, with the intermediate value of the sequence after the ordering intermediate value as the data of described predetermined number.
5. the device of a cancellation of DC offset is characterized in that, comprising:
Acquiring unit is used to obtain the data in the predetermined number of digital baseband reception;
Computing unit calculates the intermediate value of the data of described predetermined number, and with described intermediate value as current direct current offset;
Eliminate the unit, be used for deducting the data of described direct current offset as the digital baseband actual reception in the data that digital baseband receives.
6. device according to claim 5 is characterized in that, described computing unit comprises:
The mean value computation subelement is used to calculate the average M of the data of described predetermined number, and described predetermined number is N;
Quantity is determined subelement, is used for determining the number K of described N data numerical value less than described average M;
Subelement relatively, be used for comparison K with
Size;
First determines subelement, is used for
The time, will be less than the intermediate value of the maximum in K the data of average M as the data of described predetermined number;
Second determines subelement, is used for
The time, from a described N data, take out partial data according to the value of K and sort, with the intermediate value of the sequence after the ordering as the intermediate value of the data of described predetermined number.
7. device according to claim 6 is characterized in that, described second determines that subelement comprises:
The ordering subelement is used for
Taking-up is less than K the data of M, according to descending rank order;
Taking-up is greater than N-K the data of M, according to ascending rank order;
Intermediate value is chosen subelement, is used for intermediate value with the sequence after the ordering as the intermediate value of the data of described predetermined number.
8. device according to claim 5 is characterized in that,
Described computing unit specifically is used for data to described predetermined number according to ascending or descending rank order, with the intermediate value of the sequence after the ordering intermediate value as the data of described predetermined number.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200910200012 CN102082750B (en) | 2009-12-01 | 2009-12-01 | Method and device for eliminating direct current bias |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200910200012 CN102082750B (en) | 2009-12-01 | 2009-12-01 | Method and device for eliminating direct current bias |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102082750A true CN102082750A (en) | 2011-06-01 |
| CN102082750B CN102082750B (en) | 2013-12-18 |
Family
ID=44088504
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200910200012 Active CN102082750B (en) | 2009-12-01 | 2009-12-01 | Method and device for eliminating direct current bias |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102082750B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103051402A (en) * | 2013-01-21 | 2013-04-17 | 哈尔滨工业大学 | User signal detection method based on direct-current offset self-adapted frequency spectrum energy |
| CN103095619A (en) * | 2011-10-28 | 2013-05-08 | 联芯科技有限公司 | Direct current elimination method and direct current elimination device |
| CN103532891A (en) * | 2012-07-06 | 2014-01-22 | 展讯通信（上海）有限公司 | Receiver, direct current estimation method and device, and direct current elimination method and device |
| CN109361417A (en) * | 2018-11-29 | 2019-02-19 | 中电科仪器仪表有限公司 | A kind of signal processing method and system for zero intermediate frequency receiver direct current offset |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100532285B1 (en) * | 2003-09-24 | 2005-11-29 | 삼성전자주식회사 | Apparatus for cancellating dc offset in time division duplexing mode receiver |
| US7411446B2 (en) * | 2006-11-09 | 2008-08-12 | Industrial Technology Research Institute | DC offset cancellation circuit |
| US7538595B2 (en) * | 2007-05-08 | 2009-05-26 | Alcor Micro, Corp. | DC offset canceling circuit |
-
2009
- 2009-12-01 CN CN 200910200012 patent/CN102082750B/en active Active
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103095619A (en) * | 2011-10-28 | 2013-05-08 | 联芯科技有限公司 | Direct current elimination method and direct current elimination device |
| CN103095619B (en) * | 2011-10-28 | 2016-08-03 | 联芯科技有限公司 | Direct current elimination method and device |
| CN103532891A (en) * | 2012-07-06 | 2014-01-22 | 展讯通信（上海）有限公司 | Receiver, direct current estimation method and device, and direct current elimination method and device |
| CN103532891B (en) * | 2012-07-06 | 2016-09-07 | 展讯通信（上海）有限公司 | Receiver and direct current estimation method and device, direct current elimination method and device |
| CN103051402A (en) * | 2013-01-21 | 2013-04-17 | 哈尔滨工业大学 | User signal detection method based on direct-current offset self-adapted frequency spectrum energy |
| CN103051402B (en) * | 2013-01-21 | 2014-12-17 | 哈尔滨工业大学 | User signal detection method based on direct-current offset self-adapted frequency spectrum energy |
| CN109361417A (en) * | 2018-11-29 | 2019-02-19 | 中电科仪器仪表有限公司 | A kind of signal processing method and system for zero intermediate frequency receiver direct current offset |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102082750B (en) | 2013-12-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7724842B2 (en) | System and method for EVM self-test | |
| US8385910B2 (en) | Systems and methods for testing signal processing control | |
| CN101299615B (en) | Method and device for eliminating DC shifting of radio frequency receiver | |
| US8190162B2 (en) | Radar detection circuit for a WLAN transceiver | |
| US6798758B1 (en) | Method and apparatus for acquiring code synchronization in a CDMA communication system | |
| US20040148580A1 (en) | On-chip receiver sensitivity test mechanism | |
| US20040264608A1 (en) | Communication semiconductor integrated circuit, radio communication system, and adjustment method of gain and offset | |
| CN102121991A (en) | Interference suppression method and device based on BeiDou-I satellite signal reception | |
| CN102082750B (en) | Method and device for eliminating direct current bias | |
| CN101253697A (en) | A method and apparatus for qam demodulation in a generalized rake receiver | |
| CN101359921A (en) | Calibration gauge acquiring method and apparatus, automatic gain calibration method and apparatus | |
| US7324783B2 (en) | Method, arrangement and communication receiver for SNIR estimation | |
| JP2005210261A (en) | Wireless communication system and high frequency ic | |
| EP1681788A2 (en) | Radio quality estimation | |
| CN104253659B (en) | Spectrum sensing method and device | |
| CN101299616B (en) | Radio frequency receiver as well as electronic apparatus containing the same | |
| CN102833011B (en) | The method of testing of sensitivity and device | |
| US20030050017A1 (en) | Process and device for estimating the speed of movement of a mobile terminal, in particular a cellular mobile telephone | |
| CN113364479B (en) | Method for eliminating direct current bias, receiver and communication equipment | |
| CN108540151B (en) | A kind of method and device for eliminating mono-tone interference | |
| EP1653633A1 (en) | A interference power detection method in time-slot cdma system | |
| CN101009902A (en) | An independent test method for middle RF unit of the frequent spread receiver | |
| CN101426222A (en) | Signal quality estimation circuit for communication channel and method thereof, wireless receiving equipment | |
| CN102487366B (en) | Frequency deviation estimating method and device | |
| US20090046814A1 (en) | In-phase signal and quadrature signal generator of multi-port network |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| ASS | Succession or assignment of patent right |
Owner name: DATANG TELECOM TECHNOLOGY INDUSTRY HOLDING CO., LT Free format text: FORMER OWNER: LEADCORE TECHNOLOGY CO., LTD. Effective date: 20141222 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| COR | Change of bibliographic data |
Free format text: CORRECT: ADDRESS; FROM: 200233 XUHUI, SHANGHAI TO: 100191 HAIDIAN, BEIJING |
|
| TR01 | Transfer of patent right |
Effective date of registration: 20141222 Address after: 100191 Haidian District, Xueyuan Road, No. 1, No. 40, Patentee after: Datang Telecom Technology Industry Holding Co., Ltd. Address before: 200233 Shanghai, Jiang Road, No. 41, building 4, building 333 Patentee before: Leadcore Technology Co., Ltd. |