CN107294645B - Obtain method and device thereof, the maximum likelihood detection method of equivalent received signals - Google Patents
Obtain method and device thereof, the maximum likelihood detection method of equivalent received signals Download PDFInfo
- Publication number
- CN107294645B CN107294645B CN201610200885.9A CN201610200885A CN107294645B CN 107294645 B CN107294645 B CN 107294645B CN 201610200885 A CN201610200885 A CN 201610200885A CN 107294645 B CN107294645 B CN 107294645B
- Authority
- CN
- China
- Prior art keywords
- signal
- modulated
- modulated signal
- signals
- last
- 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.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
- H04L1/0045—Arrangements at the receiver end
- H04L1/0054—Maximum-likelihood or sequential decoding, e.g. Viterbi, Fano, ZJ algorithms
Landscapes
- Engineering & Computer Science (AREA)
- Artificial Intelligence (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
The present invention provides a kind of method and device thereof for obtaining equivalent received signals, wherein, signal is received the described method includes: obtaining, receiving signal includes multiple modulated signals by channel and noise jamming, made of multiple modulated signals are respectively modulated as multiple source signals, channel is indicated by channel coefficients；Obtain the desired value of other modulated signals in multiple modulated signals in addition to the last one modulated signal, wherein the last one modulated signal is the modulated signal of the last one corresponding source signal；Interference-cancellation process is carried out to signal is received according to the desired value of other modulated signals and channel coefficients；And based on the reception signal after Interference Cancellation, obtain the equivalent received signals of the last one modulated signal.The method for obtaining equivalent received signals can be compatible in the maximum likelihood detection method for demodulated signal, and can reduce the computation complexity of maximum likelihood detection method, and reduce the power consumption of receiving end.
Description
Technical field
The present invention relates to field of communication technology, in particular to a kind of method and device thereof for obtaining equivalent received signals, one
Kind maximum likelihood detection method.
Background technique
In modulation-demodulation technique, multiple binary signals are modulated respectively according to planisphere, wherein the constellation
Figure includes: QPSK, 16QAM, 64QAM, 256QAM etc..It should be noted that each planisphere includes one group of constellation point, in one group
Each constellation point indicated by multiple bits.For example, QPSK has one group of four constellation point 00,01,10 and 11, each constellation point packet
Include two bits；16QAM includes one group of 16 constellation point, and each constellation point includes four bits；64QAM includes one group of 64 star
Seat point, each constellation point include six bits.
Illustratively, in transmitting terminal, two binary signals 01 and 10 are adjusted by QPSK planisphere respectively
System, corresponding first binary signal 01 is first group of QPSK constellation point, and corresponding second binary signal 10 is second
Group QPSK constellation point.In receiving end, need to demodulate two modulated signals received respectively.During demodulation,
Need to obtain log-likelihood ratio (Log-Likelihood Ratio, LLR).
Maximum Likelihood Detection (the QR decomposition-based Maximum likelihood decomposed based on QR
Detection, QRM) method obtain LLR be used for demodulated signal, illustrate, existing QRM method is needed to each
All constellation points in group constellation point are traversed, to be obtained by calculating Euclidean distance (Euclidean distance)
LLR.When the order of modulation of the modulated signal of transmission is higher, such as 64QAM or 256QAM, obtain the computation complexity meeting of LLR
Very high, needing to calculate a large amount of Euclidean distance leads to the increase of receiving end power consumption.In addition, the calculating process of existing QRM method
It is fixed, lack the flexibility of adjusting.
Summary of the invention
The embodiment of the present invention provides a kind of method for obtaining equivalent received signals, to reduce the computation complexity of QRM method,
Reduce the power consumption of receiving end.
The embodiment of the present invention provides a kind of method for obtaining equivalent received signals, comprising: obtains and receives signal, the reception
Signal includes multiple modulated signals by channel and noise jamming, and the multiple modulated signal is respectively modulated by multiple source signals
Made of, the channel is indicated by channel coefficients；It obtains in the multiple modulated signal in addition to the last one modulated signal
The desired value of other modulated signals, wherein the last one described modulated signal is the modulated signal of the last one corresponding source signal；
Interference-cancellation process is carried out to the reception signal according to the desired value of other modulated signals and the channel coefficients；And
Based on the reception signal after the Interference Cancellation, the equivalent received signals of the last one modulated signal are obtained.
Optionally, the method for obtaining equivalent received signals further include: corresponding based on the last one described modulated signal
Channel coefficients, obtain the Signal to Interference plus Noise Ratio of the last one modulated signal；Based on signal processing performance, threshold value is obtained；By institute
The Signal to Interference plus Noise Ratio for stating the last one modulated signal is compared with the threshold value；And if the letter of the last one modulated signal
It is dry to make an uproar than being greater than the threshold value, obtain the desired value of other modulated signals.
Optionally, obtaining the threshold value includes: to establish the first corresponding table, and the described first corresponding table includes the threshold value and institute
State the corresponding relationship of signal processing performance, wherein the signal processing performance is indicated by demodulation accuracy or the bit error rate；And
According to the described first corresponding table, the threshold value is obtained.
Optionally, the desired value for obtaining other modulated signals include obtain in the multiple modulated signal except it is described most
The log-likelihood ratio of other modulated signals outside the latter modulated signal.
Optionally, the log-likelihood ratio of other modulated signals is obtained by calculating Euclidean distance.
Optionally, the desired value of other modulated signals is obtained further include: establish the second corresponding table, described second is corresponding
Table includes the corresponding relationship of the desired value of other modulated signals and the LLR ratio of other modulated signals；And
According to the second respective value table, the desired value of each modulated signal in other described modulated signals is obtained.
Optionally, if the multiple modulated signal is two modulated signals, the desired value of first modulated signal is under
Formula obtains:
Wherein, β is normalization factor, for making the desired value of first modulated signal have unit power；tanh
It is hyperbolic tangent function；LLR1,1, LLR1,2, LLR1,3, LLR1,4, LLR1,5And LLR1,6It is first modulated signal respectively
For the log-likelihood ratio of the 1st to 6 bit of constellation point.
Optionally, carrying out interference-cancellation process to the reception signal includes: to obtain the expectation of other modulated signals
The error of each of a value desired value modulated signal corresponding with the desired value；By the desired value and modulated signal
Error is compared with noise；And if the error of each desired value and modulated signal is much smaller than noise, to the reception
Interference cancellation signal processing.
Optionally, the modulation system that the multiple modulated signal respectively uses include QPSK, 16QAM, 64QAM or
256QAM。
The embodiment of the present invention also provides a kind of maximum likelihood detection method, is used for demodulated signal, the Maximum Likelihood Detection
Method is decomposed based on QR, comprising: according to the method for above-mentioned acquisition equivalent received signals, obtains the last one described modulation
The equivalent received signals of signal；Based on the equivalent received signals, the log-likelihood ratio of the last one modulated signal is obtained；
And the log-likelihood ratio based on the multiple modulated signal, demodulate the reception signal.
The embodiment of the present invention also provides a kind of device for obtaining equivalent received signals, comprising: receiver, with memory phase
Even, signal is received for obtaining, the signal that receives includes multiple modulated signals by channel and noise jamming, the multiple
Made of modulated signal is respectively modulated as multiple source signals, the channel is indicated by channel coefficients；And processor, the place
Reason device is configured for: obtaining the expectation of other modulated signals in the multiple modulated signal in addition to the last one modulated signal
Value, wherein the last one described modulated signal is the modulated signal of the last one corresponding source signal；According to other described modulation letters
Number desired value and the channel coefficients to the reception signal carry out interference-cancellation process；And based on after the Interference Cancellation
Reception signal, obtain the equivalent received signals of the last one modulated signal.
Optionally, the processor is additionally configured to: being based on before the desired value for obtaining other modulated signals
The corresponding channel coefficients of described the last one modulated signal obtain the Signal to Interference plus Noise Ratio of the last one modulated signal；Based on letter
Number process performance obtains threshold value；The Signal to Interference plus Noise Ratio of the last one modulated signal is compared with the threshold value；And if
The Signal to Interference plus Noise Ratio of the last one modulated signal is greater than the threshold value, obtains the desired value of other modulated signals.
Compared with prior art, the technical solution of the embodiment of the present invention has the advantage that
Based on the equivalent received signals of the last one corresponding modulated signal, using conventional method in the art (for example, through
Cross addition and comparator) log-likelihood ratio of available the last one modulated signal, it in this way can be to avoid to each group of constellation
All constellation points in point are traversed to obtain the log-likelihood ratio of the last one modulated signal, that is, reduce it is European away from
From calculation times.Therefore, the method for obtaining equivalent received signals can be compatible with the existing QRM for demodulated signal
In method, and the computation complexity of QRM method can be reduced, and reduce the power consumption of receiving end.
Further, the use probability of the method for obtaining equivalent received signals can be adjusted by a threshold value
Section, so that the QRM method of the compatible method for obtaining equivalent received signals can have flexibility.
Further, it in the method for obtaining equivalent received signals, when obtaining the desired value of modulated signal, uses
The method tabled look-up can reduce computation complexity in this way, and be convenient for hardware realization.
Detailed description of the invention
Fig. 1 shows the flow diagram of the method for the acquisition equivalent received signals of one embodiment of the invention；
Fig. 2 shows the flow diagrams of existing QRM method；
Fig. 3 shows the flow diagram of the QRM method of one embodiment of the invention；And
Fig. 4 shows the structural schematic diagram of the device of the acquisition equivalent received signals of one embodiment of the invention.
Specific embodiment
The embodiment of the present invention provides a kind of method for obtaining equivalent received signals, to reduce the computation complexity of QRM method,
And reduce the power consumption of receiving end.
To make the above purposes, features and advantages of the invention more obvious and understandable, with reference to the accompanying drawing to the present invention
Specific embodiment be described in detail.It should be noted that the purpose that these attached drawings are provided contribute to understand it is of the invention
Embodiment, and should not be construed as to improperly limitation of the invention.
Fig. 1 is the flow diagram of the method for the acquisition equivalent received signals of one embodiment of the invention.As shown in Figure 1,
The method for obtaining equivalent received signals includes the following steps.
101, it obtains and receives signal, the signal that receives includes multiple modulated signals by channel disturbance, the multiple
Made of modulated signal is respectively modulated as multiple source signals, the channel is indicated by channel coefficients.
In one embodiment of the invention, by taking two modulated signals as an example, the expression formula of signal is received are as follows:
Y=Rx+n, x=[x1,x2]T (1)
Wherein, Y refers to that reception signal, R refer to that channel, x refer to the practical modulated signal sent of transmitting terminal, and n refers to noise, x1Refer to first
A modulated signal and x2Refer to second modulated signal.Wherein, first modulated signal x1It is carried out by first group of constellation point
Modulation, second modulated signal x2It is modulated by second group of constellation point.It should be noted that channel R is with rectangular
Formula indicates, wherein matrix R includes channel coefficients, and it is 1 that matrix R, which is by the power of QR decomposition acquisition and noise,.
In a specific embodiment, the expression formula of signal is received are as follows:
Wherein, receiving signal Y includes first reception signal y1With second reception signal y2, andIt is letter
Road matrix includes channel coefficients r11、r12And r22, the channel matrix is to decompose to obtain by QR.It should be noted that r11It is
Corresponding first modulated signal x1Channel coefficients, r12And r22It is corresponding second modulated signal x2Channel system
Number.
103, the desired value of other modulated signals in the multiple modulated signal in addition to the last one modulated signal is obtained,
Wherein, the last one described modulated signal is the modulated signal of the last one corresponding source signal.
In one embodiment of the invention, in obtaining the multiple modulated signal in addition to the last one modulated signal
Before the desired value of other modulated signals, first the Signal to Interference plus Noise Ratio of the last one modulated signal and a threshold value to be compared
Compared with.
In the present embodiment, two sources can be modulated by planisphere QPSK, 16QAM, 64QAM, 256QAM etc. respectively
Signal is to obtain x1And x2.If first modulated signal x1With second modulated signal x2Mean power be unit
Power, i.e. power be 1 and, in receiving end, if first modulated signal x1To second modulated signal x2Interference
It being cancelled, the power of channel disturbance is much smaller than the power of the noise, in this case, second modulated signal x2Signal to Interference plus Noise Ratio
(Signal to Interference plus Noise Ratio, SINR) can be approximated to be
If the Signal to Interference plus Noise RatioGreater than one threshold value, obtains first modulated signal x1Desired value.This reality
It applies in example, to obtain the threshold value, first establishes a corresponding table, the corresponding table includes the threshold value and signal processing performance
Corresponding relationship, wherein the signal processing performance is indicated by demodulation accuracy or the bit error rate.Communication terminal is according to specific solution
The requirement for adjusting accuracy or the bit error rate, obtains corresponding threshold value by tabling look-up.Under normal circumstances, the threshold value selection, which is able to satisfy, wants
The smallest value for the signal processing performance asked, for example, can be carried out by the bit error rate or demodulation accuracy and computation complexity flat
Weighing apparatus is with the value of the determination threshold value.In research and development, especially when being emulated, using the adjustable QRM method of the threshold value
Using the probability of the method for obtaining equivalent received signals, to reduce the computation complexity of the QRM method in communication terminal.
In addition, the corresponding table can be established by the producer of communication terminal.In some embodiments, communication terminal can also pass through
Adaptive algorithm updates the corresponding table.
If Signal to Interference plus Noise RatioQRM method in the prior art acquisition pair is used with reference to Fig. 2 less than the threshold value
Number likelihood ratio.
It illustrates, with first modulated signal x1For corresponding first group of constellation point, described first group
Constellation point in constellation point is expressed as s1, first modulated signal x1For s1The log-likelihood ratio of b-th of bit
LLR1,bExpression formula are as follows:
Wherein, s2Refer to the constellation point in second group of constellation point,Refer to that b-th of bit is 1 in first group of constellation point
Constellation point,Indicate the constellation point that b-th of bit is 0 in first group of constellation point, and | | Y-Rs | |2To calculate Europe
The expression formula of formula distance, wherein s=[s1,s2]T.Similarly, second modulated signal x2For s2B-th bit
Log-likelihood ratio LLR2,bExpression formula are as follows:
Obtain first modulated signal x1With second modulated signal x2Log-likelihood ratio after, can be used for demodulate connect
The collection of letters number.From above-mentioned expression formula (3) and (4), it can be seen that calculate LLR1,bAnd LLR2,bIt needs to calculate multiple Euclidean distance, counts
Calculation amount is bigger.Therefore, one embodiment of the present of invention is according to the comparison result of above-mentioned Signal to Interference plus Noise Ratio and the threshold value, if institute
State Signal to Interference plus Noise RatioGreater than the threshold value, can carry out simplifying processing.
It illustrates, if the Signal to Interference plus Noise RatioIt, can be first according to above-mentioned formula (3) greater than the threshold value
Obtain first modulated signal x1Log-likelihood ratio LLR1,b, then obtain first modulated signal x1Desired value.
In the present embodiment, first modulated signal x1Desired value expression formula are as follows:
Wherein,Refer to first modulated signal x1Desired value, C1Refer to x1The collection of constellation point in corresponding planisphere
It closes, p (x1) it is first modulated signal x1Sending probability,Refer toReal part, andRefer toImaginary part.It needs to illustrate
, p (x1) expanded expression can be passed through by including that the expression formula of hyperbolic tangent function indicatesThen it carries out
Classification merges the method for public keys, can obtainWithSimplified expression are as follows:
And
Wherein, simplified expression (6) and (7) include for first modulated signal x1Corresponding constellation point s1Each ratio
Special log-likelihood ratio (for example, for 64QAM, first modulated signal x1Correspondence s1The log-likelihood ratio packet of each bit
Include LLR1,1、LLR1,2、LLR1,3、LLR1,4、LLR1,5And LLR1,6).It is described for constellation point s1The log-likelihood ratio of each bit
It can be obtained by expression formula (3).
It should be noted that QPSK includes one group of four constellation point 00,01,10 and 11, each constellation point includes two ratios
It is special；16QAM includes one group of 16 constellation point, and each constellation point includes four bits；64QAM includes one group of 64 constellation point, often
A constellation point includes six bits.
Wherein, tanh is hyperbolic tangent function, and the variable of the hyperbolic tangent function includes for constellation point s1Each bit
Log-likelihood ratio LLR1,b.It should be noted that hyperbolic tangent function is the function of a Monotone Bounded, so tanh
The value of function can be obtained by look-up table.In addition, β is normalization factor, for making first modulated signal x1Phase
Prestige valueWith unit power.
Therefore, according to simplified expression (6) and (7) and hyperbolic tangent function table, it can establish a corresponding table,
In, the corresponding table includes first modulated signal x1Desired valueWith for constellation point s1The log-likelihood of each bit
Compare LLR1,bCorresponding relationship, first modulated signal x is then obtained according to the respective value table1Desired valueIt needs
Illustrate, computation complexity can be reduced using the method tabled look-up, and be convenient for hardware realization.
105, the reception signal is interfered according to the desired value of other modulated signals and the channel coefficients
Counteracting processing.
In the present embodiment, first modulated signal x is obtained1Desired valueAfterwards, if the desired valueWith institute
State first modulated signal x1Error be much smaller than noise, can be subtracted from the reception signal YIt offsets and receives
The first modulated signal x arrived1For the second modulated signal x received2Caused by interfere, thus obtain pair
Answer second modulated signal x2Reception signal Y2, the reception signal Y2Expression formula are as follows:
Wherein, Y1Refer to corresponding first modulated signal x1Desired valueReception signal,
107, based on the reception signal after the Interference Cancellation, obtain the equivalent received letter of the last one modulated signal
Number.
In the present embodiment, after carrying out interference-cancellation process, maximum-ratio combing (Maximal- is carried out to expression formula (8)
Ratio Combining, MRC), to obtain corresponding second modulated signal x2Equivalent received signals y2, eff, described
Equivalent received signals y2, effExpression formula are as follows:
Wherein,It is second modulated signal x2Equivalent channel coefficient and neffIt is equivalent noise.
It illustrates, maximum-ratio combing is carried out to expression formula (8) and is referred to, to second modulated signal x2It is corresponding
Channel matrixTransposition conjugation (conjugate transpose) is carried out to obtain the channel matrix after transposition conjugationAgain by the channel matrix after transposition conjugationWith the reception signal Y2It carries out described in matrix multiple acquisition
Equivalent received signals.
It should be noted that the method for the acquisition equivalent received signals in above-described embodiment can be simultaneous with existing QRM method
Hold.Existing QRM method is compared, can reduce and calculate again by adjusting threshold value in the method for obtaining equivalent received signals
Miscellaneous degree, and reduce the power consumption of receiving end.
The embodiment of the present invention also provides a kind of Maximum Likelihood Detection (QRM) method decomposed based on QR, is used for demodulated signal.
As shown in figure 3, the QRM method includes:
301, according to the method for the acquisition equivalent received signals in above-described embodiment, obtain the last one described modulated signal
Equivalent received signals；
303, the equivalent received signals are based on, the log-likelihood ratio of the last one modulated signal is obtained；And
305, based on the log-likelihood ratio of the multiple modulated signal, demodulate the reception signal.
In one particular embodiment of the present invention, it is based on second modulated signal x2Equivalent received signals, adopt
Second modulated signal x can be obtained with conventional method (for example, by addition and comparator) in the art2It is corresponding
LLR.This way it is possible to avoid obtaining second modulated signal x using expression formula (4)2For s2The logarithm of b-th of bit
Likelihood ratio LLR2,b, that is, reduce the calculation times of Euclidean distance.Therefore, the method for obtaining equivalent received signals can be simultaneous
Hold in the existing QRM method for demodulated signal, reduce the computation complexity of QRM method, and reduces the power consumption of receiving end.
The embodiment of the present invention also provides a kind of device for obtaining equivalent received signals, comprising: receiver 401, with memory
It is connected, receives signal for obtaining, the signal that receives includes multiple modulated signals by channel and noise jamming, described more
Made of a modulated signal is respectively modulated as multiple source signals, the channel is indicated by channel coefficients；And processor 403,
The processor 403 is configured for: obtaining other modulation in the multiple modulated signal in addition to the last one modulated signal
The desired value of signal, wherein the last one described modulated signal is the modulated signal of the last one corresponding source signal；According to described
The desired value of other modulated signals and the channel coefficients carry out interference-cancellation process to the reception signal；And based on described
Reception signal after Interference Cancellation obtains the equivalent received signals of the last one modulated signal.
In one embodiment of the present of invention, before the desired value of the processor 403 other modulated signals described in obtaining,
It is also configured for: based on the corresponding channel coefficients of the last one described modulated signal, obtaining the last one described modulation letter
Number Signal to Interference plus Noise Ratio；Based on signal processing performance, threshold value is obtained；By the Signal to Interference plus Noise Ratio of the last one modulated signal with it is described
Threshold value is compared；And if the Signal to Interference plus Noise Ratio of the last one modulated signal is greater than the threshold value, obtains other described tune
The desired value of signal processed.
In one embodiment of the present of invention, it includes: to establish the first corresponding table, institute that the processor 403, which obtains the threshold value,
State the corresponding relationship that the first corresponding table includes the threshold value Yu the signal processing performance, wherein the signal processing performance is logical
Crossing demodulation accuracy or the bit error rate indicates；And according to signal processing performance and the first corresponding table, obtain the threshold value.
In one embodiment of the present of invention, the desired value that the processor 403 obtains other modulated signals includes: to obtain
Take the log-likelihood ratio of other modulated signals in the multiple modulated signal in addition to the last one described modulated signal.
In one embodiment of the present of invention, the log-likelihood ratio of other modulated signals is obtained by calculating Euclidean distance
It takes.
In one embodiment of the present of invention, the processor 403 obtains the desired value of other modulated signals further include:
The second corresponding table is established, the described second corresponding table includes the desired value and other modulated signals of other modulated signals
The corresponding relationship of LLR ratio；And according to the second respective value table, obtain each in other described modulated signals
The desired value of modulated signal.
In one embodiment of the present of invention, if the multiple modulated signal is two modulated signals, the processor 403
The desired value of first modulated signal is obtained according to following formula:
Wherein, β is normalization factor, for making the desired value of first modulated signal have unit power；tanh
It is hyperbolic tangent function；LLR1,1, LLR1,2, LLR1,3, LLR1,4, LLR1,5And LLR1,6It is first modulated signal respectively
For the log-likelihood ratio of the 1st to 6 bit of constellation point.
In one embodiment of the present of invention, the processor 403 carries out interference-cancellation process to the reception signal and includes:
Obtain the mistake of each of the desired value of other a modulated signals desired value modulated signal corresponding with the desired value
Difference；The desired value is compared with the error of modulated signal with noise；And if each desired value and modulated signal
Error be much smaller than noise, to the receptions interference cancellation signal handle.
It should be noted that configuration refers to the computer program being stored in nonvolatile memory, such as software code, firmly
Part code or the code of software and hardware combining etc., are compiled and are executed by processor.The nonvolatile memory include but
It is not limited to any kind of disk, such as floppy disk, CD, CD-ROMs and magneto-optic disk, ROMs, RAMs, EPROMs, EEPROMs, magnetic
Card or light-card or any type memory of suitable stored electrons instruction.The nonvolatile memory passes through bus and the place
Manage device connection.
Although present disclosure is as above, present invention is not limited to this.Anyone skilled in the art are not departing from this
It in the spirit and scope of invention, can make various changes or modifications, therefore protection scope of the present invention should be with claim institute
Subject to the range of restriction.
Claims (18)
1. a kind of method for obtaining equivalent received signals characterized by comprising
It obtains and receives signal, the signal that receives includes multiple modulated signals by channel and noise jamming, the multiple tune
Made of signal processed is respectively modulated as multiple source signals, the channel is indicated by channel coefficients；
Obtain the desired value of other modulated signals in the multiple modulated signal in addition to the last one modulated signal, wherein institute
State the modulated signal that the last one modulated signal is the last one corresponding source signal；
Interference-cancellation process is carried out to the reception signal according to the desired value of other modulated signals and the channel coefficients；
And
Based on the reception signal after the Interference Cancellation, the equivalent received signals of the last one modulated signal are obtained；
Wherein, the desired value of acquisition other modulated signals includes:
The Signal to Interference plus Noise Ratio of the last one modulated signal is compared with threshold value, the threshold value and signal processing performance exist
Corresponding relationship, the signal processing performance are indicated by demodulation accuracy or the bit error rate；
If the Signal to Interference plus Noise Ratio of the last one modulated signal is greater than the threshold value, the expectation of other modulated signals is obtained
Value.
2. obtaining the method for equivalent received signals as described in claim 1, which is characterized in that in the last one modulation by described in
Before the Signal to Interference plus Noise Ratio of signal is compared with the threshold value, further includes:
Based on the corresponding channel coefficients of the last one described modulated signal, the letter of acquisition the last one modulated signal is dry to make an uproar
Than；
Based on signal processing performance, the threshold value is obtained.
3. obtaining the method for equivalent received signals as claimed in claim 2, which is characterized in that obtaining the threshold value includes:
The first corresponding table is established, the described first corresponding table includes the corresponding relationship of the threshold value Yu the signal processing performance；With
And
According to the signal processing performance and the first corresponding table, the threshold value is obtained.
4. obtaining the method for equivalent received signals as described in claim 1, which is characterized in that obtain other described modulated signals
Desired value include pair for obtaining other modulated signals in the multiple modulated signal in addition to the last one described modulated signal
Number likelihood ratio.
5. obtaining the method for equivalent received signals as claimed in claim 4, which is characterized in that pair of other modulated signals
Number likelihood ratio is obtained by calculating Euclidean distance.
6. obtaining the method for equivalent received signals as claimed in claim 4, which is characterized in that obtain other described modulated signals
Desired value further include:
The second corresponding table is established, the described second corresponding table includes that the desired value of other modulated signals and other described modulation are believed
Number LLR ratio corresponding relationship；And
According to the second respective value table, the desired value of each modulated signal in other described modulated signals is obtained.
7. obtaining the method for equivalent received signals as claimed in claim 4, which is characterized in that if the multiple modulated signal is
Two modulated signals, the desired value of first modulated signal obtain according to the following formula:
Wherein, β is normalization factor, for making the desired value of first modulated signal have unit power；Tanh is double
Bent tangent function；LLR1,1, LLR1,2, LLR1,3, LLR1,4, LLR1,5And LLR1,6Be respectively first modulated signal for
The log-likelihood ratio of the 1st to 6 bit of constellation point.
8. obtaining the method for equivalent received signals as described in claim 1, which is characterized in that done to the reception signal
Disturbing counteracting processing includes:
Obtain each of the desired value of other a modulated signals desired value modulated signal corresponding with the desired value
Error；
The desired value is compared with the error of modulated signal with noise；And
If the error of each desired value and modulated signal is much smaller than noise, to reception interference cancellation signal processing.
9. obtaining the method for equivalent received signals as described in claim 1, which is characterized in that the multiple modulated signal is respectively
The modulation system used includes QPSK, 16QAM, 64QAM or 256QAM.
10. a kind of maximum likelihood detection method is used for demodulated signal, wherein the maximum likelihood detection method is based on QR points
Solution characterized by comprising
According to the method for acquisition equivalent received signals any one of in such as claim 1 to 9, obtain it is described the last one
The equivalent received signals of modulated signal；
Based on the equivalent received signals, the log-likelihood ratio of the last one modulated signal is obtained；And
Based on the log-likelihood ratio of the multiple modulated signal, the reception signal is demodulated.
11. a kind of device for obtaining equivalent received signals characterized by comprising
Receiver is connected with memory, receives signal for obtaining, the reception signal includes by channel and noise jamming
Multiple modulated signals, made of the multiple modulated signal is respectively modulated as multiple source signals, the channel passes through channel coefficients
It indicates；And
Processor, the processor are configured for:
Obtain the desired value of other modulated signals in the multiple modulated signal in addition to the last one modulated signal, wherein institute
State the modulated signal that the last one modulated signal is the last one corresponding source signal；
Interference-cancellation process is carried out to the reception signal according to the desired value of other modulated signals and the channel coefficients；
And
Based on the reception signal after the Interference Cancellation, the equivalent received signals of the last one modulated signal are obtained；
Wherein, the desired value of acquisition other modulated signals includes:
The Signal to Interference plus Noise Ratio of the last one modulated signal is compared with threshold value, the threshold value and signal processing performance exist
Corresponding relationship, the signal processing performance are indicated by demodulation accuracy or the bit error rate；
If the Signal to Interference plus Noise Ratio of the last one modulated signal is greater than the threshold value, the expectation of other modulated signals is obtained
Value.
12. device as claimed in claim 11, which is characterized in that the processor is by the last one modulated signal
Before Signal to Interference plus Noise Ratio is compared with the threshold value, it is additionally configured to:
Based on the corresponding channel coefficients of the last one described modulated signal, the letter of acquisition the last one modulated signal is dry to make an uproar
Than；
Based on signal processing performance, the threshold value is obtained.
13. device as claimed in claim 12, which is characterized in that the processor obtains the threshold value and includes:
The first corresponding table is established, the described first corresponding table includes the corresponding relationship of the threshold value Yu the signal processing performance；With
And
According to signal processing performance and the first corresponding table, the threshold value is obtained.
14. device as claimed in claim 11, which is characterized in that the processor obtains the expectation of other modulated signals
Value includes: the log-likelihood for obtaining other modulated signals in the multiple modulated signal in addition to the last one described modulated signal
Than.
15. device as claimed in claim 14, which is characterized in that the log-likelihood ratio of other modulated signals is to pass through meter
Calculate what Euclidean distance obtained.
16. device as claimed in claim 14, which is characterized in that the processor obtains the expectation of other modulated signals
Value further include:
The second corresponding table is established, the described second corresponding table includes that the desired value of other modulated signals and other described modulation are believed
Number LLR ratio corresponding relationship；And
According to the second respective value table, the desired value of each modulated signal in other described modulated signals is obtained.
17. device as claimed in claim 14, which is characterized in that if the multiple modulated signal is two modulated signals, institute
State the desired value that processor obtains first modulated signal according to the following formula:
Wherein, β is normalization factor, for making the desired value of first modulated signal have unit power；Tanh is double
Bent tangent function；LLR1,1, LLR1,2, LLR1,3, LLR1,4, LLR1,5And LLR1,6Be respectively first modulated signal for
The log-likelihood ratio of the 1st to 6 bit of constellation point.
18. device as claimed in claim 11, which is characterized in that the processor carries out Interference Cancellation to the reception signal
Processing includes:
Obtain each of the desired value of other a modulated signals desired value modulated signal corresponding with the desired value
Error；
The desired value is compared with the error of modulated signal with noise；And
If the error of each desired value and modulated signal is much smaller than noise, to reception interference cancellation signal processing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610200885.9A CN107294645B (en) | 2016-03-31 | 2016-03-31 | Obtain method and device thereof, the maximum likelihood detection method of equivalent received signals |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610200885.9A CN107294645B (en) | 2016-03-31 | 2016-03-31 | Obtain method and device thereof, the maximum likelihood detection method of equivalent received signals |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107294645A CN107294645A (en) | 2017-10-24 |
| CN107294645B true CN107294645B (en) | 2019-11-01 |
Family
ID=60087321
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610200885.9A Active CN107294645B (en) | 2016-03-31 | 2016-03-31 | Obtain method and device thereof, the maximum likelihood detection method of equivalent received signals |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107294645B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102208964A (en) * | 2011-05-25 | 2011-10-05 | 中兴通讯股份有限公司 | System and method for realizing log likelihood ratio in digital system |
| US8155233B1 (en) * | 2007-09-11 | 2012-04-10 | Marvell International Ltd. | MIMO decoding in the presence of various interfering sources |
| CN103795503A (en) * | 2014-02-28 | 2014-05-14 | 电子科技大学 | QR decomposition detection method |
| CN104243377A (en) * | 2014-09-01 | 2014-12-24 | 华为技术有限公司 | Interference suppression method and device |
| CN105453467A (en) * | 2013-10-18 | 2016-03-30 | 华为技术有限公司 | Transmission and receiving method in a wireless communication system |
-
2016
- 2016-03-31 CN CN201610200885.9A patent/CN107294645B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8155233B1 (en) * | 2007-09-11 | 2012-04-10 | Marvell International Ltd. | MIMO decoding in the presence of various interfering sources |
| CN102208964A (en) * | 2011-05-25 | 2011-10-05 | 中兴通讯股份有限公司 | System and method for realizing log likelihood ratio in digital system |
| CN105453467A (en) * | 2013-10-18 | 2016-03-30 | 华为技术有限公司 | Transmission and receiving method in a wireless communication system |
| CN103795503A (en) * | 2014-02-28 | 2014-05-14 | 电子科技大学 | QR decomposition detection method |
| CN104243377A (en) * | 2014-09-01 | 2014-12-24 | 华为技术有限公司 | Interference suppression method and device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107294645A (en) | 2017-10-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101232474B (en) | Apparatus and method for receiving signal in broadband wireless access system | |
| US8737458B2 (en) | Highly-spectrally-efficient reception using orthogonal frequency division multiplexing | |
| US8238499B2 (en) | Method and apparatus for low-complexity interference cancellation in communication signal processing | |
| US8213525B2 (en) | Method of estimating and removing noise in OFDM systems | |
| CN102144377B (en) | Channel estimation and equalization for hard-limited signals | |
| US8102930B2 (en) | Demodulation of 16-QAM, DCM data symbols using two hybrid-QPSK constellations | |
| US8295378B2 (en) | Method and system for minimum mean squared error soft interference cancellation (MMSE-SIC) based suboptimal maximum likelihood (ML) detection for multiple input multiple output (MIMO) wireless system | |
| US8767889B2 (en) | Normalization of soft bit information for FEC decoding | |
| US20100246656A1 (en) | Methods and systems for soft-bit demapping | |
| JP2007526719A (en) | Iterative channel and interference estimation and decoding | |
| CN106911374A (en) | A kind of low complexity soft exports spatial modulation detection method | |
| CN105591990B (en) | A kind of suppressing method of impulse disturbances | |
| CN101404642A (en) | Soft demodulation method for 32 ary quadrature amplitude modulation | |
| CN104301267A (en) | Multi-stage iterative detection method and device of MIMO wireless communication receiver | |
| EP2140642A1 (en) | Method and apparatus for mitigating interference in multicarrier modulation systems | |
| CN105610484B (en) | Extensive MIMO Low-complexity iterative receiver methods | |
| US20130022155A2 (en) | Enhanced lattice reduction systems and methods | |
| WO2019197657A1 (en) | Approximation of log-likelihood ratios for soft decision decoding in the presence of impulse noise channels | |
| CN109412670B (en) | Low-complexity detection method based on relaxation iteration in GSM-MBM system | |
| US20070036245A1 (en) | Methods and systems for soft-bit demapping | |
| CN102739576B (en) | Soft bit digital demodulating method and device of planisphere based on complex number space | |
| US9160578B2 (en) | Turbo equalisation | |
| CN107294645B (en) | Obtain method and device thereof, the maximum likelihood detection method of equivalent received signals | |
| Şahin et al. | Spectrally efficient iterative MU-MIMO receiver for SC-FDMA based on EP | |
| US8630375B2 (en) | Method and apparatus for received signal processing in a multi-stage receiver |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |