CN104283835A - Quadrature amplitude modulation qubit demodulation method and device - Google Patents

Quadrature amplitude modulation qubit demodulation method and device Download PDF

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CN104283835A
CN104283835A CN201310274884.5A CN201310274884A CN104283835A CN 104283835 A CN104283835 A CN 104283835A CN 201310274884 A CN201310274884 A CN 201310274884A CN 104283835 A CN104283835 A CN 104283835A
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subregion
bit
demodulated
perpendicular bisector
receiving symbol
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CN104283835B (en
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黄习文
杨�远
曹晏波
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DATANG LINKTECH INFOSYSTEM Co Ltd
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DATANG LINKTECH INFOSYSTEM Co Ltd
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/32—Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
    • H04L27/34—Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
    • H04L27/38—Demodulator circuits; Receiver circuits
    • H04L27/3809—Amplitude regulation arrangements

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Abstract

The embodiment of the invention discloses a quadrature amplitude modulation qubit demodulation method. The method includes the steps of predetermining a sub-area which each constellation point belongs to on a gray constellation complex plane corresponding to a bit position to be demodulated, wherein each sub-area corresponds to a perpendicular bisector; determining a sub-area which each constellation point containing the corresponding bit position to be demodulated and mapped by a received symbol on the gray constellation complex plane corresponding to the bit position to be demodulated; calculating the perpendicular distance between each received symbol containing the corresponding bit position to be demodulated and the corresponding perpendicular bisector, and making the distances serve as the qubit values of the bit position to be demodulated, wherein the qubit values are positive when each received symbol containing the corresponding bit position to be demodulated is located on the side, with the first bit value, of the corresponding perpendicular bisector, and the qubit values are negative when each received symbol containing the corresponding bit position to be demodulated is located on the side, with the second bit value, of the corresponding perpendicular bisector. The invention further discloses a quadrature amplitude modulation qubit demodulation device. By means of the quadrature amplitude modulation qubit demodulation method and device, the qubit demodulation efficiency can be improved.

Description

A kind of soft bit demodulation method of quadrature amplitude modulation and device thereof
Technical field
The application relates to communication technical field, particularly the device of the soft bit demodulation method of a kind of quadrature amplitude modulation (QAM) and correspondence thereof.
Background technology
Modern Communication System, for improving the availability of frequency spectrum, adopts high order modulation usually.Quadrature amplitude modulation (Quadrature Amplitude Modulation, QAM) is conventional high-order modulating, since its order of modulation M can be 4,8,16,32, can also reach more than 128,256 etc.After employing quadrature amplitude modulation, its decoding system adopts the BICM (Bit-Interleaved Coded Modulation) of Soft decision decoding usually, and this decoded mode requires that demodulator exports soft bit information.Soft bit information is weighed with the log-likelihood ratio (Log-Likelihood Ratio, LLR) receiving bit usually, that is:
LLR ( b ) = ln ( Pr ( b = 0 | r ) Pr ( b = 1 | r ) )
In above formula: r is the complex symbol received, b is certain bit in receiving symbol.
Under Gaussian white noise channel, the mode of the soft bit of prior art demodulation is: suppose at Gray's planisphere (mark signal that the corresponding QAM of each constellation point in this figure transmits concentrated, constellation point adopts the configuration of horizontal and vertical direction equally spaced square net usually) in the probability that occurs of each constellation point equal, then likelihood ratio LLR (b) obtains according to the following formula:
LLR ( b ) = ln ( Σ s ∈ S b 0 ( exp - 1 σ 2 | r - s | 2 ) Σ s ∈ S b 1 ( exp - 1 σ 2 | r - s | 2 ) )
In above formula: r is the complex symbol received, s is certain constellation point in Gray's planisphere, represent that b is the constellation point sets of 0 correspondence, represent that b is the constellation point sets of 1 correspondence, σ 2the power spectral density of white Gaussian noise.Demodulation soft bit information relates to exponent arithmetic in this manner, and operand is quite large.For this reason, in actual application, occurred a kind of abbreviation demodulation method, the method only gets one maximum in the summation formula of molecule denominator, that is:
LLR ( b ) = 1 σ 2 [ min s ∈ S b 0 ( | r - s | 2 ) - min s ∈ S b 1 ( | r - s | 2 ) ]
Exponent arithmetic is converted into the calculating of two minimum ranges by the soft bit demodulation method after simplification, using the difference of two minimum Eustachian distances as corresponding bit Soft Inform ation.Although this demodulation method no longer carries out complicated exponent arithmetic, but, also need the distance asking for each constellation point in receiving symbol and Gray's planisphere, the exponent number of quadrature amplitude modulation is higher, constellation point on Gray's constellation is just more, the amount calculated will be multiplied, and extend handling duration, thus reduce the efficiency of demodulation soft bit information.
Summary of the invention
For solving the problems of the technologies described above, the embodiment of the present application provides the device of a kind of soft bit demodulation method of quadrature amplitude modulation and correspondence thereof, with simplified operation amount, improves soft bit demodulation efficiency.
The soft bit demodulation method of the quadrature amplitude modulation that the application provides comprises:
Gray's constellation complex plane that bit to be demodulated is corresponding pre-determines subregion belonging to each constellation point, the corresponding perpendicular bisector of each subregion, the perpendicular bisector of line between the first constellation point and the second constellation point that described perpendicular bisector is that in subregion, distance default receiving symbol is nearest, described first constellation point and the second constellation point have the first bit value and the second bit value respectively;
Constellation point subregion belonging on Gray's constellation complex plane that this bit to be demodulated is corresponding that the receiving symbol determining to comprise bit to be demodulated maps;
Calculate the vertical range of the perpendicular bisector that subregion is corresponding belonging to constellation point that the receiving symbol that comprises bit to be demodulated maps to this receiving symbol on Gray's constellation complex plane, using the soft bit values of this distance as bit to be demodulated; When the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the first bit value time, this soft bit values be on the occasion of, when the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the second bit value time, this soft bit values is negative value.
Preferably, described method also comprises: when Gray's constellation complex plane exists multiple subregion, and identical for perpendicular bisector corresponding for subregion and in subregion constellation point is merged into same subregion to the subregion that the distance calculating formula of perpendicular bisector is identical.
Preferably, described method also comprises: when Gray's constellation complex plane exists multiple subregion, parallel for perpendicular bisector corresponding for subregion two subregions are merged into a subregion, or two subregions that the symbol of the soft bit values calculated by the perpendicular bisector corresponding to subregion is identical merge into a subregion.
Preferably, when carrying out 128 rank quadrature amplitude modulation, the vertical range of the perpendicular bisector that subregion is corresponding belonging to the constellation point that the receiving symbol that described calculating comprises bit to be demodulated maps to this receiving symbol on Gray's constellation complex plane, is specially the soft bit values of this distance as bit to be demodulated:
When bit to be demodulated is the first bit of receiving symbol, using the soft bit values of the real part of receiving symbol as this bit to be demodulated; When bit to be demodulated is the second bit of receiving symbol, using the soft bit values of the imaginary part of receiving symbol as this bit to be demodulated.
Preferably, if the half of the spacing of two adjacent constellation point is D, the real part r of receiving symbol x=real (r), imaginary part is r y=imag (r), then on Gray's constellation complex plane, the scope of each subregion is determined according to following table 1:
Wherein: the b in table 1 3~ b 7represent the 3rd to the 7th bit, symbol " & " in table 1, "; " expression " and with " relation, in table 1, "None" represents that corresponding bit does not exist this subregion;
Calculate the vertical range of the perpendicular bisector that subregion is corresponding belonging to constellation point that the receiving symbol that comprises bit to be demodulated maps to this receiving symbol on Gray's constellation complex plane, this distance be specially according to the formulae discovery shown in following table 2 as the soft bit values of bit to be demodulated:
Wherein: the b in table 2 3~ b 7represent the 3rd to the 7th bit, in table 2, "None" represents that corresponding bit does not exist this subregion soft bit calculating formula corresponding with this subregion.
Present invention also provides a kind of quadrature amplitude and adjust soft bit demodulation device.This device comprises: subregion determining unit belonging to subregion determining unit, receiving symbol belonging to constellation point and soft bit demodulation unit, wherein:
Described subregion determining unit, for determining subregion belonging to each constellation point on Gray's constellation complex plane that bit to be demodulated is corresponding, the corresponding perpendicular bisector of each subregion, the perpendicular bisector of line between the first constellation point and the second constellation point that described perpendicular bisector is that in subregion, distance default receiving symbol is nearest, described first constellation point and the second constellation point have the first bit value and the second bit value respectively;
Subregion determining unit belonging to described receiving symbol, the constellation point that the receiving symbol for determining to comprise bit to be demodulated maps is subregion belonging on Gray's constellation complex plane that this bit to be demodulated is corresponding;
Described soft bit demodulation unit, for calculating the vertical range of the perpendicular bisector that subregion is corresponding belonging to constellation point that the receiving symbol that comprises bit to be demodulated maps to this receiving symbol on Gray's constellation complex plane, using the soft bit values of this distance as bit to be demodulated; When the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the first bit value time, this soft bit values be on the occasion of, when the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the second bit value time, this soft bit values is negative value.
Preferably, described device comprises subregion division unit, for when Gray's constellation complex plane exists multiple subregion, identical for perpendicular bisector corresponding for subregion and in subregion constellation point is divided into same subregion to the subregion that the distance calculating formula of perpendicular bisector is identical.
Preferably, described device also comprises subregion merge cells, for when there is multiple subregion in Gray's constellation complex plane, parallel for perpendicular bisector corresponding for subregion two subregions are merged into a subregion, or two subregions that the symbol of the soft bit values calculated by the perpendicular bisector corresponding to subregion is identical merge into a subregion.
Corresponding to the bit to be demodulated in advance Gray's constellation complex plane of the embodiment of the present application carries out the corresponding perpendicular bisector of this subregion of subregion, receiving symbol as the size of the soft bit demodulated, is determined the sign of soft bit size to the distance of perpendicular bisector by the receiving symbol calculating bit to be demodulated again at different subregions.Compared with prior art, the embodiment of the present application without the need to calculating the distance of receiving symbol to all constellation point, and only calculates the distance of receiving symbol to perpendicular bisector, and calculation process process is simple, and operand reduces, thus improves the efficiency of demodulation soft bit information.
Accompanying drawing explanation
In order to be illustrated more clearly in the embodiment of the present application or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, the accompanying drawing that the following describes is only some embodiments recorded in the application, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.
Fig. 1 is the flow chart of the soft bit demodulation embodiment of the method for quadrature amplitude modulation of the application;
Fig. 2 is that the subregion of the application simplifies merging schematic diagram;
Fig. 3 is the gray mappings planisphere of 128 rank quadrature amplitude modulation;
Fig. 4 (a) ~ (g) is the b of 128 rank quadrature amplitude modulation 1~ b 7point Division schematic diagram of bit;
Fig. 5 is the structured flowchart of the quadrature amplitude modulation soft bit demodulation device embodiment of the application.
Embodiment
Technical scheme in the application is understood better in order to make those skilled in the art person, below in conjunction with the accompanying drawing in the embodiment of the present application, technical scheme in the embodiment of the present application is clearly and completely described, obviously, described embodiment is only some embodiments of the present application, instead of whole embodiments.Based on the embodiment in the application, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all should belong to the scope of the application's protection.
See Fig. 1, the figure shows the flow process of an embodiment of the soft bit demodulation method of quadrature amplitude modulation of the application.This flow process comprises:
Step S101: pre-determine subregion belonging to each constellation point on Gray's constellation complex plane that bit to be demodulated is corresponding, the corresponding perpendicular bisector of each subregion, the perpendicular bisector of line between the first constellation point and the second constellation point that described perpendicular bisector is that in subregion, distance default receiving symbol is nearest, described first constellation point and the second constellation point have the first bit value and the second bit value respectively;
Before the calculating carrying out soft bit values, the embodiment of the present application pre-determines the affiliated subregion of the constellation point on Gray's constellation complex plane, the Gray constellation complex plane corresponding due to the different bits of identical receiving symbol may be different, therefore, each point Division to Gray's constellation complex plane is corresponding with bit to be demodulated.The rule of Gray's constellation complex plane being carried out to subregion finds the receiving symbol (note: the receiving symbol comprising bit to be demodulated being different from follow-up actual reception that on complex plane, distance one is default, this default receiving symbol is the receiving symbol for carrying out subregion any position illusion in subregion) nearest there is the first bit value (such as, " 0 ") constellation point and there is the second bit value (such as, " 1 ") constellation point, then this two constellation point are connected, using the perpendicular bisector of these two constellation point lines as the foundation dividing subregion.Under normal circumstances, the subregion divided out may have multiple, and be simplified operation, the application preferably carries out certain merging and simplification to these subregions.Merge and simplify and can have multiple specific implementation, the mode that the following two kinds is concrete is provided here:
One of mode: what be about to when dividing subregion should to be divided into two subregions according to above-mentioned steps is divided into a subregion.The rule that this mode merges subregion judges whether to occur identical perpendicular bisector (hard decision line) on a complex plane and has identical soft output calculating formula (namely calculating receiving symbol identical to the range formula of perpendicular bisector), if identical, then original foundation perpendicular bisector should be divided into two subregions and be divided into a subregion.Such as, see two receiving symbols of r1, the r2 in Fig. 2, L1 is according to the perpendicular bisector that aforementioned two steps divide out, identical at the formula of the distance calculating this perpendicular bisector, the subregion dividing out according to these two receiving symbols can be considered as a subregion like this.
Mode two: after point Division is complete, according to certain rule, the multiple subregions having divided out are simplified.The rule simplifying subregion can be investigate the relation between different perpendicular bisector, also can investigate the symbol of the soft bit values that different perpendicular bisector calculates.For the former, if two perpendicular bisectors are parallel to each other, then the subregion that these two perpendicular bisectors divide out can be merged into a subregion.Such as, r1, r3 two receiving symbols in Fig. 2, the perpendicular bisector that r1 is corresponding is the perpendicular bisector that L1, r3 are corresponding is L2, and two parallel, merged into a subregion.For the latter, if the symbol of the soft bit values calculated just is being or is being negative, then the subregion that these two perpendicular bisectors divide out can merged into a subregion.Such as, r4, r5 two receiving symbols in Fig. 2, their perpendicular bisector is respectively L4, L3, and these two receiving symbols are all in 1 this side of two perpendicular bisectors, and namely the symbol of soft bit values is just, and therefore, can be merged into a subregion.
Step S102: constellation point subregion belonging on Gray's constellation complex plane that this bit to be demodulated is corresponding that the receiving symbol determining to comprise bit to be demodulated maps;
Step S103: the vertical range calculating the perpendicular bisector that subregion is corresponding belonging to constellation point that the receiving symbol that comprises bit to be demodulated maps to this receiving symbol on Gray's constellation complex plane, using the soft bit values of this distance as bit to be demodulated; When the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the first bit value time, this soft bit values be on the occasion of, when the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the second bit value time, this soft bit values is negative value.
The present embodiment determines two constellation point on Gray's constellation complex plane that bit to be demodulated is corresponding, then carry out complex plane according to two constellation point and carry out subregion, receiving symbol as the size of the soft bit demodulated, is determined the sign of soft bit size to the distance of perpendicular bisector by the receiving symbol calculating bit to be demodulated again at different subregions.Compared with prior art, the present embodiment without the need to calculating the distance of receiving symbol to all constellation point, and only calculates the distance of receiving symbol to perpendicular bisector, and calculation process process is simple, and operand reduces, thus improves the efficiency of demodulation soft bit information.
In order to the technical scheme of the application is clearly described, below with one more specifically example explain.See Fig. 3, the figure shows Gray's planisphere of the quadrature amplitude modulation on 128 rank (full bit), each point on this planisphere represents a possible receiving symbol, and each receiving symbol comprises 7 bit: b 1, b 2, b 3, b 4, b 5, b 6, b 7.The process obtaining the demodulation result of each soft bit mainly comprises three steps:
The first step: the subregion judging receiving symbol place;
Second step: calculate the distance of receiving symbol to the perpendicular bisector in this region, using the size of this distance as soft bit;
3rd step: when receiving symbol is positioned at ' 1 ' side of perpendicular bisector, the symbol of soft bit size is just, when being positioned at ' 0 ' side of perpendicular bisector, the symbol of soft bit size is negative.
For the b in 128QAM 1bit, the subregion dividing out according to the above-mentioned first step as shown in Fig. 4 (a), due to b 1two corresponding subregions are positioned at the left and right of the complex plane imaginary axis, and therefore, the imaginary axis is perpendicular bisector, and in this case, calculating receiving symbol can be simplified to the distance of perpendicular bisector: using the soft bit values of the real part of receiving symbol as this bit to be demodulated.
For the b in 128QAM 2bit, the subregion dividing out according to the above-mentioned first step as shown in Fig. 4 (b), due to b 2two corresponding subregions are positioned at the upper and lower of complex plane real axis, and therefore, real axis is perpendicular bisector, and in this case, calculating receiving symbol also can be simplified to the distance of perpendicular bisector: using the soft bit values of the imaginary part of receiving symbol as this bit to be demodulated.
For the b in 128QAM 3~ b 7bit, the subregion dividing out according to the above-mentioned first step is as shown in Fig. 4 (c) ~ 4 (g).Suppose that the half of the spacing of two adjacent constellation point in Gray's planisphere is D, the complex symbol of reception is r, makes r x=real (r), r y=tmag (r), is respectively receiving symbol real part and imaginary part, on this basis, and b 3~ b 7the computing formula of soft bit values and the corresponding relation of subregion as shown in the table.
Wherein: the b in table 1 3~ b 7represent the 3rd to the 7th bit, symbol " & " in table 1, "; " expression " and with " relation, in table 1, "None" represents that corresponding bit does not exist this subregion.
Wherein: the b in table 2 3~ b 7represent the 3rd to the 7th bit, in table 2, "None" represents that corresponding bit does not exist this subregion soft bit calculating formula corresponding with this subregion.
It should be noted that: in the planisphere that Gray code maps, b 3, b 4, b 5, b 6, b 7receiving symbol at other quadrants, about reference axis full symmetric, therefore, can be transformed into first quartile by the absolute value asking for actual situation portion and calculate by corresponding distribution, thus simplifies calculating, reduces workload.
Foregoing describes the embodiment of the method for the soft bit demodulation of quadrature amplitude modulation of the application in detail.Accordingly, present invention also provides quadrature amplitude and adjust soft bit demodulation device embodiment.See Fig. 5, the figure shows the composition structure that quadrature amplitude adjusts soft bit demodulation device embodiment.This device comprises: subregion determining unit 502 belonging to subregion determining unit 501, receiving symbol belonging to constellation point and soft bit demodulation unit 503, wherein:
Subregion determining unit 501 belonging to constellation point, for determining subregion belonging to each constellation point on Gray's constellation complex plane that bit to be demodulated is corresponding, the corresponding perpendicular bisector of each subregion, the perpendicular bisector of line between the first constellation point and the second constellation point that described perpendicular bisector is that in subregion, distance default receiving symbol is nearest, described first constellation point and the second constellation point have the first bit value and the second bit value respectively;
Subregion determining unit 502 belonging to receiving symbol, the constellation point that the receiving symbol for determining to comprise bit to be demodulated maps is subregion belonging on Gray's constellation complex plane that this bit to be demodulated is corresponding;
Soft bit demodulation unit 503, for calculating the vertical range of the perpendicular bisector that subregion is corresponding belonging to constellation point that the receiving symbol that comprises bit to be demodulated maps to this receiving symbol on Gray's constellation complex plane, using the soft bit values of this distance as bit to be demodulated; When the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the first bit value time, this soft bit values be on the occasion of, when the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the second bit value time, this soft bit values is negative value.
In said apparatus embodiment, in order to simplified operation, can carry out merging to subregion and simplify, this merging simplification can be carried out when delimiting subregion in advance, also can divide out at subregion to merge the multiple subregions meeting certain condition afterwards.Under the former situation, the preferred described device of the application comprises subregion division unit 504, for when Gray's constellation complex plane exists multiple subregion, identical for perpendicular bisector corresponding for subregion and in subregion constellation point is divided into same subregion to the subregion that the distance calculating formula of perpendicular bisector is identical.In the later case, the preferred described device of the application also comprises subregion merge cells 505, when there is multiple subregion for Gray's constellation complex plane, parallel for perpendicular bisector corresponding for subregion two subregions are merged into a subregion, or two subregions that the symbol of the soft bit values calculated by the perpendicular bisector corresponding to subregion is identical merge into a subregion.
It should be noted that: easy in order to what describe, the difference that what above-described embodiment of this specification and the various distortion implementations of embodiment stressed is all with other embodiments or mode of texturing, between each situation identical similar part mutually see.Especially, for several improved procedures of device embodiment, because it is substantially similar to embodiment of the method, so describe fairly simple, relevant part illustrates see the part of embodiment of the method.Each unit of device embodiment described above or can may not be and physically separates, and both can be positioned at a place, or under also can being distributed to multiple network environment.In actual application, some or all of unit wherein can be selected according to the actual needs to realize the object of the present embodiment scheme, and those of ordinary skill in the art, when not paying creative work, are namely appreciated that and implement.
The above is only the embodiment of the application; it should be pointed out that for those skilled in the art, under the prerequisite not departing from the application's principle; can also make some improvements and modifications, these improvements and modifications also should be considered as the protection range of the application.

Claims (8)

1. the soft bit demodulation method of quadrature amplitude modulation, it is characterized in that, the method comprises:
Gray's constellation complex plane that bit to be demodulated is corresponding pre-determines subregion belonging to each constellation point, the corresponding perpendicular bisector of each subregion, the perpendicular bisector of line between the first constellation point and the second constellation point that described perpendicular bisector is that in subregion, distance default receiving symbol is nearest, described first constellation point and the second constellation point have the first bit value and the second bit value respectively;
Constellation point subregion belonging on Gray's constellation complex plane that this bit to be demodulated is corresponding that the receiving symbol determining to comprise bit to be demodulated maps;
Calculate the vertical range of the perpendicular bisector that subregion is corresponding belonging to constellation point that the receiving symbol that comprises bit to be demodulated maps to this receiving symbol on Gray's constellation complex plane, using the soft bit values of this distance as bit to be demodulated; When the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the first bit value time, this soft bit values be on the occasion of, when the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the second bit value time, this soft bit values is negative value.
2. method according to claim 1, it is characterized in that, described method comprises: when Gray's constellation complex plane exists multiple subregion, and identical for perpendicular bisector corresponding for subregion and in subregion constellation point is merged into same subregion to the subregion that the distance calculating formula of perpendicular bisector is identical.
3. method according to claim 1, it is characterized in that, described method also comprises: when Gray's constellation complex plane exists multiple subregion, parallel for perpendicular bisector corresponding for subregion two subregions are merged into a subregion, or two subregions that the symbol of the soft bit values calculated by the perpendicular bisector corresponding to subregion is identical merge into a subregion.
4. method according to claim 1, is characterized in that, when carrying out 128 rank quadrature amplitude modulation, calculating comprises the receiving symbol of bit to be demodulated to the vertical range of perpendicular bisector, is specially by the soft bit values of this distance as bit to be demodulated:
When bit to be demodulated is the first bit of receiving symbol, using the soft bit values of the real part of receiving symbol as this bit to be demodulated; When bit to be demodulated is the second bit of receiving symbol, using the soft bit values of the imaginary part of receiving symbol as this bit to be demodulated.
5. method according to claim 1, is characterized in that, if the half of the spacing of two adjacent constellation point is D, and the real part r of receiving symbol x=real (r), imaginary part is r y=imag (r), then on Gray's constellation complex plane, the scope of each subregion is determined according to following table 1:
Wherein: the b in table 1 3~ b 7represent the 3rd to the 7th bit, symbol " & " in table 1, "; " expression " and with " relation, in table 1, "None" represents that corresponding bit does not exist this subregion;
Calculate the receiving symbol that the comprises bit to be demodulated vertical range to perpendicular bisector, this distance be specially according to the formulae discovery shown in following table 2 as the soft bit values of bit to be demodulated:
Wherein: the b in table 2 3~ b 7represent the 3rd to the 7th bit, in table 2, "None" represents that corresponding bit does not exist this subregion soft bit calculating formula corresponding with this subregion.
6. quadrature amplitude adjusts a soft bit demodulation device, it is characterized in that, this device comprises: subregion determining unit belonging to subregion determining unit, receiving symbol belonging to constellation point and soft bit demodulation unit, wherein:
Described constellation point determining unit, for determining subregion belonging to each constellation point on Gray's constellation complex plane that bit to be demodulated is corresponding, the corresponding perpendicular bisector of each subregion, the perpendicular bisector of line between the first constellation point and the second constellation point that described perpendicular bisector is that in subregion, distance default receiving symbol is nearest, described first constellation point and the second constellation point have the first bit value and the second bit value respectively;
Subregion determining unit belonging to described receiving symbol, the constellation point that the receiving symbol for determining to comprise bit to be demodulated maps is subregion belonging on Gray's constellation complex plane that this bit to be demodulated is corresponding;
Described soft bit demodulation unit, for calculating the vertical range of the perpendicular bisector that subregion is corresponding belonging to constellation point that the receiving symbol that comprises bit to be demodulated maps to this receiving symbol on Gray's constellation complex plane, using the soft bit values of this distance as bit to be demodulated; When the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the first bit value time, this soft bit values be on the occasion of, when the described receiving symbol comprising bit to be demodulated be positioned at perpendicular bisector comprise the side of the second bit value time, this soft bit values is negative value.
7. device according to claim 6, it is characterized in that, described device comprises subregion division unit, for when Gray's constellation complex plane exists multiple subregion, identical for perpendicular bisector corresponding for subregion and in subregion constellation point is divided into same subregion to the subregion that the distance calculating formula of perpendicular bisector is identical.
8. device according to claim 6, it is characterized in that, described device also comprises subregion merge cells, for when there is multiple subregion in Gray's constellation complex plane, parallel for perpendicular bisector corresponding for subregion two subregions are merged into a subregion, or two subregions that the symbol of the soft bit values calculated by the perpendicular bisector corresponding to subregion is identical merge into a subregion.
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CN106534037A (en) * 2016-10-31 2017-03-22 西安烽火电子科技有限责任公司 Soft modulation method for high order modulation signals
CN106534037B (en) * 2016-10-31 2019-09-03 西安烽火电子科技有限责任公司 A kind of soft demodulating method of high order modulation signal
CN109302264B (en) * 2017-07-24 2021-04-02 展讯通信（上海）有限公司 Method, apparatus and computer readable medium for maximum likelihood detection
CN109302264A (en) * 2017-07-24 2019-02-01 展讯通信（上海）有限公司 The method, apparatus and computer-readable medium of Maximum Likelihood Detection
CN109756275A (en) * 2017-11-03 2019-05-14 深圳市中兴微电子技术有限公司 A kind of demodulation method and demodulating equipment
CN109756275B (en) * 2017-11-03 2021-10-15 深圳市中兴微电子技术有限公司 Demodulation method and demodulation device
CN110505359B (en) * 2018-05-18 2020-10-23 中国科学院上海高等研究院 Non-uniform modulation and demodulation method, system, medium and terminal in wireless broadcast communication system
CN110505359A (en) * 2018-05-18 2019-11-26 中国科学院上海高等研究院 Non-uniformly modulated demodulation method, system, medium and terminal in wireless broadcast communication system
CN113055330A (en) * 2018-06-14 2021-06-29 福建星海通信科技有限公司 Low-complexity soft decision method based on phase amplitude characteristic
CN113055330B (en) * 2018-06-14 2023-10-20 福建星海通信科技有限公司 Low-complexity soft decision method based on phase amplitude characteristics
CN115242588A (en) * 2021-04-25 2022-10-25 大唐移动通信设备有限公司 Signal demodulation processing method, communication device, and storage medium
CN115242588B (en) * 2021-04-25 2024-04-16 大唐移动通信设备有限公司 Signal demodulation processing method, communication device, and storage medium
CN116915570A (en) * 2023-08-03 2023-10-20 成都爱瑞无线科技有限公司 Soft demodulation method and device based on APSK modulation, communication equipment and storage medium
CN116915570B (en) * 2023-08-03 2023-12-12 成都爱瑞无线科技有限公司 Soft demodulation method and device based on APSK modulation, communication equipment and storage medium

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