CN101179358B - Method and apparatus for implementing space-time coding - Google Patents

Abstract

The invention relates to a method for realizing space-time coding. The method includes the following detailed steps: the space-time coding is conducted for bit data according to modulation mode and the space-time coded data is conducted constellation point planar qualification mapping. The invention also provides a device for realizing space-time coding. The invention utilizes the limited modulation point operation result from space-time coding transmission matrix operation, so that space-time coding needs not to be conducted after modulation, and space-time coding and modulation process can be carried out simultaneously. Therefore, bit digitals of the data being processed in the digital devices can be lowered, and power consumption of digital processing devices can be reduced.

Description

Space Time Coding implementation method and device

Technical field

The present invention relates to moving communicating field, especially a kind of Space Time Coding implementation method and device.

Multiple-input and multiple-output (Multiple Input Multiple Output, be called for short MIMO) technology be the 4th generation wireless communication system one of key technology, the MIMO technology can be brought diversity gain, spatial multiplexing gain, interference cancellation gain and array coding gain.Alamouti Space Time Coding (Space Time Coding; Space Time Coding; Abbreviation STC) (Space Time Coding is proposed by Alamouti the earliest) is a kind of MIMO technology that can bring diversity gain; By (the Institute of Electrical and Electronics Engineers of American Institute of Electronic Engineer; Abbreviation IEEE) IEEE802.16 agreement, third generation partner program (Third Generation Partnership Project; It is one of technological that the Long Term Evolution plan (Ultra Mobile Broadband is called for short UMB) that is called for short Long Term Evolution plan (Long Term Evolution is called for short LTE), the 3GPP2 tissue of 3GPP tissue waits the next generation wireless communication agreement to be adopted as standard MIMO.The STC technology can also be extended to space-frequency coding, with hierarchical space-time code (Layered Space Time Code; Abbreviation LST) the mixing Space Time Coding of structure associating; The latter can obtain diversity gain on the basis that obtains spatial multiplexing gain, the international communication forums such as Long Term Evolution plan of these Long Term Evolution plans of all being organized as IEEE802.16,3GPP by the technological MIMO technology that derived of STC, 3GPP2 tissue are to the candidate of next generation wireless communication technical standard or selected scheme.High speed development along with very lagre scale integrated circuit (VLSIC) and Digital Signal Processing; As how lower power consumption and resource consumption with the MIMO technical application at application-specific integrated circuit (ASIC) (Application Specific Intergrated Circuits; Abbreviation ASIC), field programmable gate array (Field Programmable Gate Array; Be called for short FPGA) and digital signal processor (Digital Singnal Processor is called for short DSP) to wait on the digital processing device be to realize one of key that MIMO is technological.

Usually the operation principle that realizes Space Time Coding is: Bit data is input to modulator modulates, be input to the Space Time Coding device through the data after the modulators modulate and carry out Space Time Coding, launched by antenna through Space Time Coding device encoded data.

Generally; Modulation system has QPSK (Quadrature Phase Shift Keying; Abbreviation QPSK), multiple modulation systems such as 16 state quadrature amplitude modulation (Quadrature Amplitude Modulation is called for short QAM), 64QAM, 256QAM.Need when the bit data are modulated earlier Bit data to be mapped on the constellation point of planisphere, adopt the digital processing device to realize, subsequently these constellation point are quantized (quantizing promptly is the data that the data volume of low number of bits changed into the higher bit figure place).Shown in Figure 1 is planisphere under the QPSK modulation system, the planisphere under the 16QAM modulation system shown in Figure 2.

Be the principle of example explanation modulation below with 16QAM.Under perfect condition, the constellation point of the N in the N-QAM modulation system can be modulated log ₂N Bit data, 16 constellation point can be modulated 4 Bit datas in the 16QAM modulation system, and are as shown in Figure 2 for the planisphere under the 16QAM modulation system, and 16 sampling points are represented the combination of 16 kinds of amplitudes and phase place in the planisphere.16QAM is the two-dimensional modulation technology; When realizing, adopt the mode of quadrature amplitude modulation; The amplitude of the projection modulation homophase carrier wave of a constellation point on the I coordinate in the 16QAM planisphere; The amplitude of the projection modulation orthogonal carrier wave on the Q coordinate is exactly required phase-modulated signal with these two amplitude-modulated signal additions then.What receiving terminal can be according to the bit signal that the amplitude and the phase place of signal are judged transmission just after receiving this amplitude modulation phase-modulated signal.For example, among Fig. 2, a string Bit data is 0000, is mapped to be S in the 16QAM planisphere ₀Symbolic point, S ₀Symbolic point is at the amplitude of the projection modulation homophase carrier wave of I reference axis, S ₀Symbolic point is in the amplitude of the projection modulation orthogonal carrier wave of Q reference axis, the signal after then in-phase signal and orthogonal signalling addition being obtained modulating.

Bit data 0000 waiting for transmission is mapped as constellation point S through the 16QAM planisphere ₀, constellation point S ₀Can represent that its real part is the projection at the I axle with plural form, the I axis data can adopt 16 bit quantizations; Its imaginary part is the projection at the Q axle, and the Q axis data can adopt 16 bit quantizations, quantizes back S ₀Can represent with 32 Bit datas.According to the method for existing techniques in realizing Space Time Coding noted earlier, the data 0000 of 4 bits have become the number of constellation points of 32 bits according to S after ovennodulation ₀, data bit width increases, then with S ₀Be input to and carry out Space Time Coding in the Space Time Coding device, be input to the data bit width after data bit width in the Space Time Coding device will keep modulation.Realize Space Time Coding if adopt the digital processing device; Inter-process bandwidth in the Space Time Coding device needs to increase so; Can cause the increase of Space Time Coding device resource overhead, highway width increase, memory space increase, power consumption to increase like this; And the subsequent treatment after the Space Time Coding (for example adopts OFDM (Orthogonal Frequency Division Multiple Access after the Space Time Coding; Abbreviation OFDMA) the data bit width subchannel permutation technology in) also will increase, and cause digital processing device resource overhead to increase.

Below only with under the 16QAM modulation system; Also there is same problem for other in the problem that the data bit width that exists the data bit width increase of modulation back to cause the Space Time Coding device to handle increases like the Space Time Coding implementation under the modulation systems such as QPSK, 64QAM and 256QAM.Because the implementation method of Space Time Coding is that the data after ovennodulation are carried out Space Time Coding in the prior art; And in the digital processing device, Bit data can be caused the increase of data bit width after ovennodulation, so caused the increase of the data bit width of Space Time Coding processing.

Summary of the invention

The embodiment of the invention provides a kind of Space Time Coding implementation method to the deficiency that prior art exists, and can reduce the data bit width that the Space Time Coding device is handled, and reduces the power consumption of Space Time Coding device, improves the processing speed of Space Time Coding device.

The embodiment of the invention provides a kind of Space Time Coding implementation method, comprising:

Match according to modulation system bit data; Carry out Space Time Coding according to what store in advance through the Bit data of pairing and through the Bit data that through the mapping relations between the Bit data of bits of encoded process is matched after the Space Time Coding basic operation; To pass through data map Cheng Wei behind the Space Time Coding through the constellation point plane quantized data before the bits of encoded.

The embodiment of the invention also provides a kind of Space Time Coding implement device, comprising:

The Space Time Coding module is used for Bit data is carried out Space Time Coding according to modulation system; Quantization modules is connected with said Space Time Coding module, is used for just through the constellation point plane quantized data before the process of the data map Cheng Wei behind the Space Time Coding bits of encoded;

Said Space Time Coding module comprises: memory module, be used to store through the Bit data of pairing with pass through after the Space Time Coding basic operation through the mapping relations between the Bit data of bits of encoded; Matching module is used for Bit data is matched according to modulation system; Mapping block; Be connected with said memory module with said matching module respectively, be used for the said matching module data based memory module after through pairing store through the Bit data of pairing with through being mapped to the data behind the process Space Time Coding through the mapping relations between the Bit data of bits of encoded after the Space Time Coding basic operation.

The present invention utilizes limited modulation point result's under the Space Time Coding matrix operation finiteness; When the laggard line space of modulation, do not encode; To modulate with Space Time Coding and carry out simultaneously, thereby be reduced in the number of bits of the data of handling in the digital device, reduce digital processing device power consumption.

Description of drawings

Shown in Figure 1 is planisphere under the QPSK modulation system;

Planisphere under the 16QAM modulation system shown in Figure 2;

Shown in Figure 3 is Space Time Coding implementation method embodiment one flow chart of the present invention;

Shown in Figure 4 is the concrete grammar flow chart of step 1 among Fig. 3;

Shown in Figure 5 for obtaining said Bit data and space-time coded data mapping relations method flow diagram;

Shown in Figure 6 is Alamouti launch scenario sketch map;

Shown in Figure 7 is 16QAM constellation point data map sketch map;

Shown in Figure 8ly adopt under the QPSK modulation system bits of encoded sketch map in the Space Time Coding implementation method for two antennas in the IEEE802.16e agreement of the present invention;

Shown in Figure 9 is Space Time Coding implement device embodiment one structural representation of the present invention.

Embodiment

Below through specific embodiment and combine accompanying drawing that the present invention is done further detailed description.

Shown in Figure 3 is Space Time Coding implementation method embodiment one flow chart of the present invention, specifically comprises:

Step 1, carry out Space Time Coding according to modulation system bit data;

Step 2, quantize mapping to carry out the constellation point plane through the data of Space Time Coding.

The present embodiment difference with the prior art is; Present embodiment is that the bit data are carried out Space Time Coding and modulation simultaneously; Rather than first bit data are carried out Space Time Coding again after ovennodulation as prior art; So the method for present embodiment compared with prior art can reduce the data bit width that the Space Time Coding device is handled, thereby reduce the power consumption of Space Time Coding device, improve the processing speed of Space Time Coding device.

Be illustrated in figure 4 as the concrete grammar flow chart of step 1 among Fig. 3, carry out Space Time Coding according to modulation system bit data in the step 1 and be specially:

Step 11, match according to modulation system bit data;

Step 12, the Bit data that process is matched according to the Bit data and the space-time coded data mapping relations of storage in advance carry out Space Time Coding.

Store and also comprise before said Bit data and the space-time coded data mapping relations and obtain Bit data and space-time coded data mapping relations, be illustrated in figure 5 as and obtain said Bit data and space-time coded data mapping relations method flow diagram, be specially:

Step 121, the Bit data that obtains under the said modulation system according to modulation system are right;

Step 122, with said Bit data to being mapped to the number of constellation points certificate under the said modulation system;

Step 123, to said number of constellation points according to carrying out the Space Time Coding basic operation, and quantize mapping to carrying out the constellation point plane through the data after the Space Time Coding basic operation;

Step 124, to said through the Space Time Coding basic operation and passed through the data that the constellation point plane quantizes after the mapping and carried out bits of encoded.

Principle below in conjunction with the instance illustrated in detail embodiment of the invention one.

The Alamouti Space Time Coding is a kind of two antennas transmit diversity schemes, is illustrated in figure 6 as Alamouti launch scenario sketch map, and at t constantly (t refers to any moment), two signals send from two antennas simultaneously, is signal x from what first transmitting antenna sent ₁, from second transmitting antenna send for signal x ₂, at the t+T moment (T is a given symbol period in the Space Time Coding), signal-x ₂ ^*Send signal x from first transmitting antenna ₁ ^*Send from second transmitting antenna, so the transmission matrix of two antennas transmit diversity scheme Alamouti Space Time Coding is shown in formula (1):

$A=\left[\begin{array}{cc}{x}_1& {x_2}^{*}\\ x_2& {x_1}^{*}\end{array}\right]---\left(1\right)$

Can adopt multiple modulation system in the Alamouti Space Time Coding implementation method modulation step under two antennas; With the 16QAM modulation system is example, and for the 16QAM modulation system, 16 constellation point once can be modulated the data of 4 bits; A symbolic point in per 4 Bit data constellation points; Two inputs are arranged, so in a given symbol time, it for example is 00110000 that the Space Time Coding device receives 8 Bit datas among the transmission matrix A.These 8 Bit datas are matched by the 16QAM modulation system, and the set of forming through the data after the pairing is designated as B, i.e. B={b ₃b ₂b ₁b ₀| 0000; 0011}; The element of any one 4 bit in the set B is carried out the constellation point mapping; Element 0000 in the set B is corresponding 1+j1 point in planisphere as shown in Figure 2, and 1-j3 point in the element 0011 corresponding planisphere shown in Figure 2 among the B so just can obtain the mapping F:b from set B to set M ₃b ₂b ₁b ₀→ s=I+jQ, for example b ₃b ₂b ₁b ₀=0000 → s=I+jQ=1+jb ₃b ₂b ₁b ₀=0011 → s=I+jQ=1-3j.

Next all elements among the pair set M carries out transmission matrix $\left[\begin{array}{cc}{x}_1& {x_2}^{*}\\ x_2& {x_1}^{*}\end{array}\right]$ In basic operation, and the data that will pass through after the Space Time Coding basic operation quantize, the set that the result who obtains forms is designated as N.Wherein, the basic operation in the matrix A is the negate conjugation of plural number and asks conjugation.For example,

s＝I+jQ＝1-3j→s ^*＝1+3j，-s ^*＝-1-3j

s＝I+jQ＝1+j→s ^*＝1-j，-s ^*＝-1+j

For bit through the result who obtains after the Space Time Coding basic operation be to 0000 and 0011:

$\left[\begin{array}{cc}1+j& -1-3j\\ 1-3j& 1-j\end{array}\right]$

The data volume that to pass through then behind the Space Time Coding changes into the more data of higher bit figure place, and this quantification is the quantification that the horizontal ordinate in the constellation point plane (being I, the Q axle among Fig. 2) data are carried out, and quantizes so be referred to as the constellation point plane.Common quantification length is 16.The set that result after the quantification forms is designated as N, then N={s|I+jQ}.The data-measuring that wherein specifically how will pass through after the Space Time Coding basic operation is 16 unified regulations, and can stipulate that here 1 usefulness 0x200 representes, 3 usefulness 0x600 represent that-1 usefulness 0xFE00 representes that-3 usefulness 0xFA00 represent (0x representes to use 16 systems).Data 1+j1 through after the Space Time Coding basic operation can be expressed as 0x200+j0x200; The 1-3j point can be expressed as 0x200+j0xFA00, and-1-3j can be expressed as 0xFE00+j0xFA00, and 1-j can be expressed as 0x200+j0xFE00; So far; Can obtain mapping, be designated as G, G:M → N from set M to set N.For example,

$G:1+j,1-3j\&RightArrow;\left[\begin{array}{cc}0x200+j0x200& 0\mathrm{<figure-callout\; id="00"\; label="xFE"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">xFE</figure-callout>}00+\mathrm{<figure-callout\; id="0"\; label="j"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">j</figure-callout>}0\mathrm{<figure-callout\; id="00"\; label="xFA"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">xFA</figure-callout>}00\\ 0x200+\mathrm{<figure-callout\; id="0"\; label="j"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">j</figure-callout>}0\mathrm{<figure-callout\; id="00"\; label="xFA"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">xFA</figure-callout>}00& 0x200+0\mathrm{<figure-callout\; id="00"\; label="xFE"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">xFE</figure-callout>}00\end{array}\right]$

Through each element in the matrix that obtains after the G mapping promptly is the element among the set N.All elements among the pair set N carries out bits of encoded then.Can know through each element in the matrix that obtains after the G mapping and can in planisphere as shown in Figure 7, find corresponding point; As shown in Figure 7; Shown in Figure 7 is 16QAM constellation point data map sketch map, and the constellation point in the 16QAM modulation system has completeness to the transmission matrix of Alamouti Space Time Coding.In the present embodiment only with 0000 and 0011 bit to being that example is illustrated; 4 all bits maybe to always having 16 kinds; Promptly 0000,0001,0010,0011,0100,0101,0110,0111,1000,1001,1010,1011,1100,1101,1110,1111; The Bit data that each is possible is to being mapped as a number of constellation points certificate, and then according to the computing among the transmission matrix A, calculated result is also these 16 kinds possible Bit data centerings.So can use ceil (log ₂Size (N))=ceil (log ₂16)=4 carry out the element among the bits of encoded set N, wherein, the number of element among Size (N) the expression set N, ceil representes to round up.For example:

0x200+j0x200→0000

0xFE00+j0xFA00→1011

0x200+j0xFA00→0011

0x200+j0xFE00→0010

The set of the data that the element among the pair set N carries out obtaining after the bits of encoded is designated as Sbit, so far can obtain the mapping from N to Sbit, is designated as H, H:N → Sbit.

Data in the set B can be obtained S set bit through F, G, H after shining upon, the mapping from set B to S set bit is designated as T, T:B → Sbit.For example, to 0000 and 0011, mapping just can obtain the data of 44 bits, T:0000,0011 → 0000,0011,0010,1011 afterwards through T for two bits.

So far, can obtain a Bit data and space-time coded data mapping relations.

With the Space Time Coding of having accomplished the bit data behind the Bit data process mapping T, then with the inverse mapping H of the data among the S set bit through H ^-1Bit data is mapped to the number of constellation points certificate that 16 systems quantize, for example,

0000→0x200+j0x200

1011→0xFE00+j0xFA00

0011→0x200+j0xFA00

0010→0x200+j0xFE00

To pass through mapping H ^-1Promptly accomplished modulation step afterwards.

Above explanation is used for explaining how to obtain a Bit data and space-time coded data mapping relations; The step that obtains Bit data and space-time coded data mapping relations is carried out before the Space Time Coding carrying out in advance; When in the Space Time Coding implement device of reality, realizing the said space-time coding method of the embodiment of the invention; For a Bit String 00000011; After matching is 0000 and 0011; These two data are directly realized that through being stored in Space Time Coding in advance Bit data and the mapping of space-time coded data mapping relations in the device can obtain 4 outputs 0000,0011,1011,0010, right for the data of any two 4 bits, can both obtain 4 outputs according to this Bit data and space-time coded data mapping relations.These 4 outputs are specially: at t constantly, and first transmitting antenna output, 0000, the second transmitting antenna output 0011, at t+T constantly, first transmitting antenna output, 1011, the second transmitting antennas output 0010.

From above with Alamouti Space Time Coding under two antennas be example carry out to finding out the detailed description of embodiment one; Bit data is mapped to the number of constellation points certificate; Then number of constellation points being carried out bits of encoded according to carrying out after the basic operation of transmission matrix, only is to have set up a kind of Bit data through pairing and passed through after the Space Time Coding basic operation through a kind of mapping relations between the Bit data of bits of encoded.The Bit data that passes through pairing is input to the back dateout that can obtain the Space Time Coding device according to these mapping relations in the transmission matrix; Need be in prior art the modulated process Bit data not just be carried out Space Time Coding after with the data representation of high quantization through such mapping; Only need the data of two 4 bits are obtained through mapping the data of 44 bits in the Space Time Coding device; And if with the method for prior art; After ovennodulation, carry out Space Time Coding again; The Space Time Coding device need be handled the data of two 32 bits so, so the described method of the embodiment of the invention can reduce the bit wide of Space Time Coding device deal with data, reduces the power consumption of Space Time Coding device.

Adopt the QPSK modulation with two antennas in the IEEE802.16e agreement below, it is example that Space Time Coding adopts C matrix radiation pattern, and the principle of the embodiment of the invention one is described.

The transmission matrix C of two antenna Space Time Coding is shown in formula (2) in the IEEE802.16e agreement:

$C=\frac{1}{\sqrt{1+r^2}}\left[\begin{array}{cc}{S}_i+\mathrm{jr}\&CenterDot;S_{i+3}& r\&CenterDot;S_{i+1}+S_{i+2}\\ S_{i-1}-r\&CenterDot;S_{i+2}& \mathrm{jr}\&CenterDot;S_i+S_{i+3}\end{array}\right]---\left(2\right)$

Wherein, $r=\frac{-1+\sqrt{5}}{2}\&ap;0.618,$ S _iBe i modulation symbol.

Under the QPSK modulation system; Once manageable bit number is 2; A symbolic point among per 2 Bit data constellation figure, C matrix need four input data, so in a given symbol time; The Space Time Coding implement device receives from 8 Bit datas of channel encoder output, for example is 00011011.These 8 Bit datas are matched by the QPSK modulation system, and the set of forming through the data after the pairing is designated as B ', i.e. B '={ b ₁b ₀| 00,01,10,11}.Then with set B ' in the element of any one 2 bit carry out the constellation point mapping, will pass through the set that the data after the constellation point mapping form and be designated as M ', promptly M '={ s|I+jQ}, as can be seen from Figure 2,00 corresponding 1+j1 (is designated as S ₁), 01 corresponding 1-j1 (is designated as S ₂), 10 correspondences-1+j1 (is designated as S ₃), 11 correspondences-1-j1 (is designated as S ₄).So far obtain from set B ' to the mapping F ' of M ', F ': B ' → M '.

All elements among the pair set M ' carries out the computing of C matrix then, and the set that the result who obtains forms is designated as N '.With S ₁, S ₂, S ₃, S ₄Bring in the C matrix, obtain

$C=\frac{1}{\sqrt{1+r^2}}\left[\begin{array}{cc}{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">S</figure-callout>}}_1+\mathrm{jr}\&CenterDot;S_4& r\&CenterDot;{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">S</figure-callout>}}_2+S_3\\ S_2-r\&CenterDot;{\mathrm{<figure-callout\; id="3"\; label="S"\; filenames="S2007101792328E00031.png"\; state="\{\{state\}\}">S</figure-callout>}}_3& \mathrm{jr}\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">S</figure-callout>}}_1+S_4\end{array}\right]$

Set N ' can be expressed as $N\text{'}=\{\&ForAll;a,b\&Element;M\text{'},\frac{a<figure-callout\; id="1"\; label="+\; Jrb"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">+</figure-callout>\mathrm{Jrb}}{\sqrt{1+{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2}},\frac{\mathrm{Ra}+\mathrm{<figure-callout\; id="1"\; label="b"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">b</figure-callout>}}{\sqrt{1+{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2}},\frac{a-\mathrm{<figure-callout\; id="1"\; label="Rb"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">Rb</figure-callout>}}{\sqrt{1+{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2}},r=\frac{-1+\sqrt{5}}{2}\},$ Wherein a, b can be any elements among the set M '.In digital device, plural number is quantified as 16 usually, specifically how to be quantified as 16 ununified regulations; Here can use the high 1 bit representation sign bit in 16,6 bit representation integer parts, 9 minimum bit representation fractional parts; The employing complement of two's two's complement representes that 1 usefulness 0x200 representes so, and-1 usefulness 0xFE00 representes; For any decimal q, can get round (q*2 ⁹) after, convert 16 system data into.Wherein, round rounds after representing to round up.For example, for a plural 3.1-2.3j, can be quantized into 3.1-2.3j=round (3.1*2 with 16 systems ⁹)-j (2.3*2 ⁹)=1578-1178j=0x633+0xFB66j.In digital device, according to above-mentioned quantitative relationship, set N ' can be expressed as

$N^{\&prime;}=\left\{n\right|\&ForAll;a,b\&Element;M^{\&prime;},n=\mathrm{round}(\frac{a<figure-callout\; id="1"\; label="+\; jrb"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">+</figure-callout>\mathrm{jrb}}{\sqrt{1+{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2}}*2^9),n=\mathrm{round}(\frac{\mathrm{ra}+\mathrm{<figure-callout\; id="1"\; label="b"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">b</figure-callout>}}{\sqrt{1+{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2}}*2^9),n=\mathrm{round}(\frac{a-\mathrm{<figure-callout\; id="1"\; label="rb"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">rb</figure-callout>}}{\sqrt{1+{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2}}*2^9),r\&ap;0.618\}$

So far, can obtain mapping, be designated as G ' from set M ' to N '.For example,

$G^{\&prime;}:a=1-\mathrm{<figure-callout\; id="1"\; label="j"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">j</figure-callout>}1,b=-1+\mathrm{<figure-callout\; id="1"\; label="j"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">j</figure-callout>}1\&RightArrow;\{n=\mathrm{round}(\frac{a<figure-callout\; id="1"\; label="+\; jrb"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">+</figure-callout>\mathrm{jrb}}{\sqrt{1+{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}^2}}*2^9)=\mathrm{round}(\frac{1-\mathrm{<figure-callout\; id="1"\; label="j"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">j</figure-callout>}1+j*0.618*(-1+j)}{\sqrt{1+{0.618}^2}}*2^9)=166-705j$

$n=\mathrm{round}\left(\frac{\mathrm{ra}+\mathrm{<figure-callout\; id="1"\; label="b"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">b</figure-callout>}}{\sqrt{1+r^2}}\right)=\mathrm{round}(\frac{0.618*(1-j)-1+\mathrm{<figure-callout\; id="1"\; label="j"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">j</figure-callout>}1}{\sqrt{1+{0.618}^2}}*2^9)=-166+166j,$

$n=\mathrm{round}\left(\frac{a-\mathrm{<figure-callout\; id="1"\; label="rb"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">rb</figure-callout>}}{\sqrt{1+r^2}}\right)=\mathrm{round}(\frac{(1-j)-0.618*(-1+j1)}{\sqrt{1+{0.618}^2}}*2^9)=705-705j\}.$

Can find out that set N ' is a finite aggregate, all carries out calculated result all in set N ' through being input to behind the process of 2 Bit datas after the pairing mapping F ' in the Matrix C.A, b can get any element among the set M ' among the set N '; The element number of set M ' is 4; Because all 2 Bit datas are mapped to number of constellation points according to 4 kinds of possibilities are also arranged to always having 4 kinds of possibilities with it, a can get four numbers like this; B also can get four numbers, so the element number of set N ' is 16.Can adopt ceil (log ₂Size (S))=ceil (log ₂16)=4 the element among the Bit data pair set N ' quantizes, and the result after the quantification is designated as Sbit '.So far obtain gathering the mapping of N ', be designated as H ', for example H ' to Sbit ': n=-166-166j → 0010, for another example: H ': n=166+705j → 0101.To gather data among the N ', to carry out bits of encoded as shown in Figure 8, shown in Figure 8ly adopts under the QPSK modulation system bits of encoded sketch map in the Space Time Coding implementation method for two antennas in the IEEE802.16e agreement of the present invention.

With set B ' in data can obtain S set bit ' after through F ', G ', H ' mapping, will be from set B ' be designated as T ', T ' to the mapping of S set bit ': B ' → Sbit '.For example, through the pairing after set B ' in element be 01,10,10,10, all elements that will collect among the B ' is mapped to number of constellation points certificate: 00 → S ₁→ 1+j1,10 → S ₂→-1+j1,10 → S ₃→-1+j1,10 → S ₄→-1+j1 carries out computing with number of constellation points according to being brought into then in the Matrix C, the data that will pass through then after the C matrix operation are carried out bits of encoded, are specially:

$C=\frac{1}{\sqrt{1+r^2}}\left[\begin{array}{cc}{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">S</figure-callout>}}_1+\mathrm{jr}\&CenterDot;S_4& r\&CenterDot;{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="S2007101792328E00011.png"\; state="\{\{state\}\}">S</figure-callout>}}_2+S_3\\ S_2-r\&CenterDot;{\mathrm{<figure-callout\; id="3"\; label="S"\; filenames="S2007101792328E00031.png"\; state="\{\{state\}\}">S</figure-callout>}}_3& \mathrm{jr}\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="S2007101792328E00011.png,S2007101792328E00031.png"\; state="\{\{state\}\}">S</figure-callout>}}_1+S_4\end{array}\right]$

$=\frac{1}{\sqrt{1+{0.618}^2}}\left[\begin{array}{cc}(1+j1)+j*0.618*(-1+j1)& 0.618*(-1+j1)+(-1+j1)\\ (-1+j1)-0.618*(-1+j1)& j*0.618*(1+j1)+(-1+j1)\end{array}\right]$

$\&RightArrow;\left[\begin{array}{cc}166-705j& -705+705\mathrm{<figure-callout\; id="166"\; label="j"\; filenames="S2007101792328E00041.png"\; state="\{\{state\}\}">j</figure-callout>}\\ 166+166j& -166+705j\end{array}\right]\&RightArrow;\left[\begin{array}{cc}0111& 1100\\ 0000& 0100\end{array}\right].$

So far, can obtain another Bit data and space-time coded data mapping relations.

With the Space Time Coding of having accomplished the bit data behind the Bit data process mapping T '.Need the data among the S set bit ' be passed through the inverse mapping H ' of H ' then ^-1Bit data is mapped to the interior data of constellation point face (being constellation point plane shown in Figure 8) that 16 systems quantize, for example,

0010→-166-166j

0101→166+705j，

Through H ' ^-1Promptly accomplished the step of modulation afterwards.

Above explanation is used for explaining how to obtain another Bit data and space-time coded data mapping relations; The step that obtains another Bit data and space-time coded data mapping relations is carried out before the Space Time Coding carrying out in advance; When in the digital device of reality, realizing the said space-time coding method of the embodiment of the invention; For a Bit String 01101010; After matching is 01,10,10,10; These 4 bits are realized that through Space Time Coding the Bit data and the mapping of space-time coded data mapping relations of storing in the device can obtain 4 outputs 0111,0000,1100,0100 to direct, right for the data of any 42 bits, can both obtain 4 outputs according to this Bit data and space-time coded data mapping relations.

Need to prove " modulation " related in the embodiment of the invention mainly be meant with Bit data be mapped to number of constellation points according to and with number of constellation points according to quantizing; Adopt the QPSK modulation for two antennas in the above IEEE802.16e agreement; Space Time Coding adopts in the Space Time Coding implementation method under the C matrix radiation pattern, and the Bit data that will pass through pairing is mapped to number of constellation points and reaches the data that will pass through bits of encoded at last according to this and carry out H ' ^-1Just be equivalent to accomplish the step of modulation after these steps of inverse operation, it is to carry out simultaneously with the step of Space Time Coding that a step is arranged in the modulation step, so be appreciated that to Space Time Coding in the present embodiment and modulation and carry out simultaneously.

Adopt the QPSK modulation for two antennas in the above IEEE802.16e agreement; Space Time Coding adopts in the Space Time Coding implementation method under the C matrix radiation pattern, adopts the embodiment of the invention one described method, need the data map of 42 bits be become the data of 44 bits; If but the method for employing prior art; Need handle the data of 4 32 bits, thus the said space-time coding method of the embodiment of the invention with respect to prior art, the data bit width that the Space Time Coding device need be handled significantly reduces; Can reduce the power consumption of Space Time Coding device, improve the data processing speed of Space Time Coding device.

If the step that after through Space Time Coding device coding, also has subchannel to interweave then can also quantize to carry out the operation that subchannel interweaves before the mapping after the Space Time Coding step and to carry out the constellation point plane through the data behind the Space Time Coding.Subchannel interweave (Sub-Channel Permutation, be also referred to as sometimes subchannel arrange) be a kind of diversity technique among the OFDMA.Its purpose is that subchannel is mapped in the different physical frequencies sections, through behind the mobile channel, makes receiving terminal obtain frequency diversity gain.Step adjustment Space Time Coding step that subchannel is interweaved and the data map that will pass through bits of encoded are between the data step without bits of encoded; Can overcome because the data bit width increase defective that the data processing bit wide increases when causing subchannel to interweave after the modulation, reduce the power consumption of subchannel interleaving treatment device.

After the Space Time Coding step and to carrying out the constellation point plane, quantize the step that mapping step can also be inserted other processing data information before through the data behind the Space Time Coding; Be not limited to the subchannel step that interweaves; Through the step of these processing data information being adjusted to after the Space Time Coding step and being quantized before the mapping step to carry out the constellation point plane through the data behind the Space Time Coding, to avoiding since in the data processing step that the data bit width increase causes after the modulation data processing bit wide increase.

Be illustrated in figure 9 as Space Time Coding implement device embodiment one structural representation of the present invention; Specifically comprise: Space Time Coding module 21; Be used for Bit data is carried out Space Time Coding according to the modulation system certificate, Bit data can be obtained through chnnel coding by channel encoder; Quantization modules 22, the Bit data that Space Time Coding module 21 is exported is quantized into through the data that the constellation point plane quantizes of having passed through after the Space Time Coding basic operation.Wherein, Space Time Coding module 21 specifically can comprise: memory module 211 is used for stored bits data and space-time coded data mapping relations; Matching module 212 is used for Bit data is matched according to modulation system; Mapping block 213; Be connected with said memory module 211 with said matching module 212 respectively, be used for Bit data and the space-time coded data mapping relations of said matching module 212 through data based memory module 211 storages after matching are mapped to through the data behind the Space Time Coding.

What should explain at last is: above embodiment is only in order to explaining technical scheme of the present invention, but not to its restriction; Although with reference to previous embodiment the present invention has been carried out detailed explanation, those of ordinary skill in the art is to be understood that: it still can be made amendment to the technical scheme that aforementioned each embodiment put down in writing, and perhaps part technical characterictic wherein is equal to replacement; And these are revised or replacement, do not make the spirit and the scope of the essence disengaging various embodiments of the present invention technical scheme of relevant art scheme.

Claims (7)

1. a Space Time Coding implementation method is characterized in that, comprising:

Match according to modulation system bit data;

Carry out Space Time Coding according to what store in advance through the Bit data of pairing and through the Bit data that through the mapping relations between the Bit data of bits of encoded process is matched after the Space Time Coding basic operation;

To pass through data map Cheng Wei behind the Space Time Coding through the constellation point plane quantized data before the bits of encoded.

2. Space Time Coding implementation method according to claim 1; It is characterized in that; Store said Bit data through pairing and pass through after the Space Time Coding basic operation through before the mapping relations between the Bit data of bits of encoded; Through the mapping relations between the Bit data of bits of encoded, specifically comprise after also comprising the Bit data that obtains the process pairing and passing through the Space Time Coding basic operation:

It is right to obtain said Bit data through pairing according to modulation system;

With said Bit data to being mapped to the number of constellation points certificate under the said modulation system;

Said number of constellation points certificate is carried out the Space Time Coding basic operation, and quantize mapping carrying out the constellation point plane through the data after the Space Time Coding basic operation;

, obtain after said Bit data through pairing and the basic operation of process Space Time Coding through the mapping relations between the Bit data of bits of encoded through the Space Time Coding basic operation and passed through the data that the constellation point plane quantizes after the mapping and carried out bits of encoded said.

3. Space Time Coding implementation method according to claim 1 is characterized in that, saidly also comprises that according to modulation system bit data channel encoder carries out the step of output Bit data after the chnnel coding before matching.

4. Space Time Coding implementation method according to claim 2; It is characterized in that, said to said through the Space Time Coding basic operation and passed through the constellation point plane and quantize data after the mapping and carry out bits of encoded and specifically comprise: to through the Space Time Coding basic operation and passed through the constellation point plane and quantize data after the mapping and carry out the data bit width of bits of encoded and be no less than ceil (log ₂Size (S)), wherein S is said through the Space Time Coding basic operation and passed through the set that the constellation point plane quantizes the data after the mapping, and Size (S) is the data number in the S set, and ceil representes to round up.

5. Space Time Coding implementation method according to claim 1; It is characterized in that; The Bit data that through the mapping relations between the Bit data of bits of encoded process is matched after the Bit data of the process pairing that said basis is stored in advance and the basic operation of process Space Time Coding carries out after the Space Time Coding; To pass through data map Cheng Wei behind the Space Time Coding through before the constellation point plane quantized data before the bits of encoded, also comprise the step of processing data information.

6. Space Time Coding implementation method according to claim 5 is characterized in that, the step of said processing data information is specially subchannel and interweaves.

7. a Space Time Coding implement device is characterized in that, comprising:

The Space Time Coding module is used for Bit data is carried out Space Time Coding according to modulation system;

Quantization modules is connected with said Space Time Coding module, is used for the data map Cheng Wei behind the process Space Time Coding through the constellation point plane quantized data before the bits of encoded;

Said Space Time Coding module comprises:

Memory module, be used to store through the Bit data of pairing with pass through after the Space Time Coding basic operation through the mapping relations between the Bit data of bits of encoded;

Matching module is used for Bit data is matched according to modulation system;

Mapping block; Be connected with said memory module with said matching module respectively, be used for said matching module through the Bit data of pairing according to memory module store through the Bit data of pairing with through being mapped to the data behind the process Space Time Coding through the mapping relations between the Bit data of bits of encoded after the Space Time Coding basic operation.

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