CN110995401B - OFDM-IM carrier activation selection method - Google Patents
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- H04L5/00—Arrangements affording multiple use of the transmission path
- H04L5/0001—Arrangements for dividing the transmission path
- H04L5/0003—Two-dimensional division
- H04L5/0005—Time-frequency
- H04L5/0007—Time-frequency the frequencies being orthogonal, e.g. OFDM(A), DMT
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- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
- H04L27/2601—Multicarrier modulation systems
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- H—ELECTRICITY
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- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
- H04L27/2601—Multicarrier modulation systems
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- H—ELECTRICITY
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- H04L5/00—Arrangements affording multiple use of the transmission path
- H04L5/0091—Signaling for the administration of the divided path
- H04L5/0096—Indication of changes in allocation
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Abstract
The invention discloses an OFDM-IM carrier activation selection method, and relates to the field of wireless communication. Adopting a method of maximizing the selection of the combined gain carrier to realize the self-adaptive block OFDM-IM system, wherein the combined gain is the weighted product of the diversity gain and the transmission rate of the system, and the weighted value omega belongs to [0,1 ]]. The invention determines the subcarrier number combination, the sub-activated carrier number combination and the subcarrier combination selection of the OFDM-IM system containing G sub-blocks, namely
(wherein
Is a vector [ T ] containing the number of carriers of each sub-block 1 ,T 2 ,…,T G ] T ，
Is a vector [ K ] containing the number of carriers of each sub-block 1 ,K 2 ,…,K G ] T ) Therefore, the performance of the OFDM-IM system can be improved.
Description
Technical Field
The invention relates to the field of wireless communication, in particular to an OFDM-IM carrier activation selection method.
Background
In the past, now and in the future, wireless communication technologies with faster transmission rates and higher reliability and lower cost are the inevitable demands of social development and the core indicators for the continuous search of breakthroughs by technicians. Orthogonal frequency division multiplexing (OFDM-IM) technology based on index modulation proposed in recent years combines the advantages of orthogonal modulation high-speed transmission while effectively combating ISI and the advantages of index modulation low sensitivity to frequency offset and phase noise, and lower peak-to-average ratio, and is one of the current popular research directions.
The core idea of the OFDM-IM technology is to introduce the concepts of index modulation and subcarrier blocks in the frequency domain, and divide transmission information into two parts, wherein index bit information determines and activates a part of subcarriers, and the rest information is transmitted by the activated subcarriers in the form of MPSK constellation modulation symbols. Research shows that OFDM-IM improves the sensitivity of the system to frequency deviation, and simultaneously the Bit Error Rate (BER) performance at the same frequency spectrum efficiency is better than that of the traditional OFDM.
Compared with the traditional modulation mode, the OFDM-IM only activates partial carriers, the possibility of reducing the system spectrum efficiency and the transmission rate exists, and meanwhile, the diversity of the selection of the carrier activation combination brings a challenge to the determination of a system scheme.
Therefore, those skilled in the art are dedicated to develop a technical solution for improving system performance by determining subcarrier number combination, subcarrier activation number combination and subcarrier combination selection in the block OFDM-IM system mode.
Disclosure of Invention
In view of the above-mentioned drawbacks of the prior art, the technical problem to be solved by the present invention is to provide a new scheme for activating carriers of a block OFDM-IM system to improve system performance.
In order to achieve the above object, the present invention provides an OFDM-IM carrier activation selection method, which is characterized in that a method of maximizing the selection of a joint gain carrier is adopted to realize an adaptive block OFDM-IM system, the joint gain is a weighted product of a system diversity gain and a transmission rate, and a weighting value ω ∈ [0,1 ].
Further, the method comprises the following steps:
step 2, initializing a sub-block r, and setting the initial activated carrier number K for the sub-block r r To 1, an initial maximum diversity gain v is set max Setting an initial value T of the number of carriers r Is T max /G；
Step 3, determining the upper bound Sup { K) of the number of the r activated carriers of the sub-block r }；
Step 4, calculating the transmission rate B of the current system r If said B is r Greater than B min Then returning to the current K r Value as minimum number of active carriers K min Otherwise, increment the K r Repeating step 4 to recalculate B r ；
Step 5, setting the K r Value of Sup { K r And calculating the diversity gain v of the current r sub-block r If the diversity gain v is r Greater than the system diversity gain lower limit v min Then returning to the current K r Value as maximum number of active carriers K max And executing step 7, otherwise executing step 6;
step 6, updating the current carrier number T r Value of T r -ν r If said T is r Not more than (K) r +1)(ν max +1), then said K is decremented r And returning to the step 5 to calculate the v r Otherwise, directly returning to the step 4 to calculate the v r ；
Step 7, setting the initial maximum diversity gain value v of the system max ＝ν min +1, setting the initial active carrier number K of the sub-block r r ＝K max ；
Step 8, calculating and updating the current transmission rate B r Calculating the current r sub-block diversity gain v r ；
Step 9, if the carrier number T is currently r Is greater than or equal to (K) r +1)(ν max +1) and the current said rate B r Greater than B min If yes, jumping to execute the step 11;
step 10, decrementing the initial activation carrierNumber K r If the number of the initial active carriers K r Greater than the minimum number of active carriers K min If yes, jumping back to the step 8, otherwise, jumping to the step 13;
step 11, judging the v r Whether greater than v min If not, updating the T r Value and said B r The value is counted and the step 8 is skipped;
step 12, updating the v according to the calculation result max Maximum joint gain U max And combinations [ T r ,K r ]；
Step 13, updating and storing the optimal carrier combination of the block OFDM-IM system
Wherein
Is a vector [ T ] containing the number of carriers of each sub-block 1 ,T 2 ,…,T G ] T ，
Is a vector [ K ] containing the number of carriers of each sub-block 1 ,K 2 ,…,K G ] T And incrementing the value of sub-block r;
step 14, judging the relation between the current subblock r and the subblock number G, and returning to the step 2 if the subblock r is not larger than the subblock number G;
Step 15, outputting the carrier optimal combination
Further, the initial maximum diversity gain v in step 2 max A number greater than 1.
Further, Sup { K) in step 3 r The calculation formula is as follows,
further, in step 4B is r Is calculated by the formula
Further, the diversity gain v of r sub-block in step 5 r Is calculated by the formula v r ＝d o,r (T r ,K r ) Wherein d is o,r Is composed of
Further, said B in step 8 r Is calculated by the formula
Further, the diversity gain v of r sub-block in step 8 r Is calculated by the formula v r ＝d o,r (T r ,K r )。
Further, the T is updated in step 11 r Value, formula T r ＝T r -ν r (ii) a Updating the B r Value of the formula B r ＝B r -1。
Further, the calculation formula of the joint gain is
The maximum joint gain U max The value takes the maximum value of the joint gain U.
The invention achieves the technical effect that the OFDM-IM system performance can be improved by determining the subcarrier number combination, the subcarrier activation number combination and the selection of the subcarrier combination.
The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, the features and the effects of the present invention.
Drawings
FIG. 1 is a flow chart of the present invention;
fig. 2 is a structural diagram of a transmitting module of a partitioned OFDM-IM system according to an embodiment of the present invention.
Detailed Description
The preferred embodiments of the present invention will be described below with reference to the accompanying drawings for clarity and understanding of technical contents. The present invention may be embodied in many different forms of embodiments and the scope of the invention is not limited to the embodiments set forth herein.
The invention aims to solve the problem of optimal combination and selection of the carrier number of the partitioned OFDM-IM system and improve the diversity gain or transmission rate of the system according to the actual requirement. The embodiment of the invention assumes that the system is in a block OFDM-IM mode and the block G is known, and of course, the invention can be adjusted according to the needs without excluding the possibility that the value of G is 1, and assumes that the lower limit B of the transmission rate of the system is the lower limit B in the environment min And a system diversity gain lower limit v min It is known that the total number of carriers for this environment is assumed to be unknown but has an upper limit of N max Optimal networking modes based on optimal transmission rates, optimal diversity gain, or optimal joint gain requirements are now sought.
As shown in fig. 1, this figure shows an application scenario of the present embodiment: a transmitter model of a partitioned OFDM-IM system. The transmitter contains a total of N subcarriers, divided into G sub-blocks. Corresponding to the input m-bit information, the system sequentially sends Pr (r is 1, 2.. gth, G) bit information to the ith sub-block respectively, namely 
P for the distributor to transmit to the r sub-block r Front in bit
The bits are used as index modulation information to determine the number and combination of activated carriers in the sub-blocks, and the rest
The bits are modulated by active carriers into constellation symbols for sub-block signal transmission, obviously
For the sub-block r (r ═ 1,2, 3.., G), the transmitted information x r (c,p r ) We can express as:
t in equation (1) represents a transpose operation, T r Representing the number of carriers contained in the sub-block r, including active and silent sub-carriers. For any one of
The value is 0 when the sub-carrier is in a silent state, and M-order constellation symbols after modulation according to input bits are in an initial and active state. Knowing that each sub-block transmits data, the information X transmitted by one OFDM-IM frame can be represented as:
x(c,b)＝{X 1 ,X 2 ,…,X G } (2)
the information contained by X corresponds to an N-point IFFT. Now consider the OFDM-IM frame transmission bit and sub-block transmission bit number relationship. According to the binary transmission characteristics, the number of carriers and the number of active carrier combinations must be a power of 2, i.e. there are:
wherein Sr represents the r-th OFDM-IM subblock activating carrier combination number under the premise of binary specification,
indicating that when all possible combinations of Kr out of Tr sub-carriers in the r-th sub-block are selected for activation, 
Denotes an integer not exceeding x. Similarly, Pr as mentioned above can also be calculated in the same way, i.e.
M represents the constellation modulation order (M2, 4,16,32 … …) for the active subcarrier transmission information.
Without loss of generality, after index mapping and constellation mapping are completed, the OFDM-IM system converts data in parallel/in series, converts frequency domain data into a time domain through N-point IFFT, and then adds CP to complete data processing of a baseband. At the receiving end, after sampling, discarding the CP, and performing FFT, we can represent the received OFDM-IM block as:
wherein Pt is the transmitting power, and K is the number of the activated subcarriers of the OFDM-IM system.
For the sub-block r of the OFDM-IM system, the number of activated carriers and the choice of carriers are various. Given number of active carriers K r Optionally in combination with
In the actual optional combination, however, due to the nature of digital transmission
Of one kind, i.e. having a r It can be seen that the combined selection and dropping scheme is uncertain, and to quantify the selection of the carrier transmission performance, we can introduce the concept of diversity gain for OFDM-IM subblock r:
the transmission rate Br of the OFDM-IM subblock r is given by:
From the above analysis, it can be seen that the system carrier andcombining of active carriers
The determination of the diversity gain and the transmission rate of the system or the joint gain of the two also affects the improvement of the sensitivity of the system to frequency offset, the spectrum efficiency, and other issues of concern of the communication system.
According to the flow shown in fig. 2, a specific embodiment of the adaptive block OFDM-IM system based on maximizing the joint gain carrier selection is provided, and the process includes the following steps:
Step 2, T max Assignment N max According to
Determining the upper bound Sup { K } of the number of r active carriers in the sub-block r Is 31, and the initial activation carrier number K of the sub-block is set r The value is 1;
step 3, setting an initial T r Value T max Calculating the current transmission rate
Is 7, is not greater than the set minimum transmission rate, then K r Updating the value 2;
step 4, K is more than or equal to 2 r ≤Sup{K r Calculating the current transmission rate in turn
Until the first time the transmission rate is met, at which time K r The value is updated to 27 and the current value is assigned to K min ，B r A value of 86;
step (ii) of5. Setting the initial active carrier number K of sub-blocks r Value is Sup { K r And d, calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 1; is not more than the set diversity gain lower limit v min Then T is r The value is updated to T r -ν；
Step 6, judging the current T r Value and (K) r +1)(ν min +1), the former being small, then K r Value is Sup { K r }-1＝30；
Step 7, T r Value T max Calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 1; is not more than the set diversity gain lower limit v min Then T is r The value is updated to T r -ν，63；
Step 8, judging the current T r Value and (K) r +1)(ν min +1), the former not being smaller than the latter, calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 1; is not more than the set diversity gain lower limit v min Then T is r The value is updated to T r -ν，62；
Step 9, judging the current T r Value and (K) r +1)(ν min +1), the former not being smaller than the latter, calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 1; is not more than the set diversity gain lower limit v min Then T is r The value is updated to T r -ν，61；
Step 10, judging the current T r Value and (K) r +1)(ν min +1), the former being small, then K r Value of K r -1＝29；
Step 11, T r Value T max Calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 1; is not more than the set diversity gain lower limit v min Then T is r The value is updated to T r -ν，63；
Step 12, judging the current T r Value and (K) r +1)(ν min +1), the former not being smaller than the latter, calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 1; if the set diversity gain lower limit vmin is not more than the set diversity gain lower limit vmin, then T r The value is updated to T r -ν，62；
Step 13, judging the current T r Value and (K) r +1)(ν min +1), the former not being smaller than the latter, calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 1; is not more than the set diversity gain lower limit v min Then T is r The value is updated to T r -ν，61；
Step 14, judging the current T r Value and (K) r +1)(ν min +1), the former not being smaller than the latter, calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 1; is not more than the set diversity gain lower limit v min Then T is r The value is updated to T r -ν，60；
Step 15, judging the current T r Value and (K) r +1)(ν min +1), the former not being smaller than the latter, calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 1; is not more than the set diversity gain lower limit v min Then T is r The value is updated to T r -ν，59；
Step 16, judging the current T r Value and (K) r +1)(ν min +1), the former being small, then K r Value of K r -1＝28；
Step 17, T r Value T max Calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 2; greater than the set diversity gain lower limit v min Then update K max The value is the current K r A value of 28;
step 18, for K min ≤K r ≤K max I.e. 27. ltoreq.K r ≦ 28, performing the following steps:
step 19, current K r A value of 28, T r Value of T max The diversity gain v is 2; calculating the current system transmission rate
To 87, calculateCurrent joint gain value U r Updating the currently best selection combination [ T ] r ,K r ]Updating the current maximum joint gain value U max ；T r The value is updated to T r -ν，62；
Step 20, judging the current T r Value and (K) r +1)(ν min +1), the former not being smaller than the latter, calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 1; is not more than the set diversity gain lower limit v min Then T is r The value is updated to T r -ν，61；
Step 21, judging the current T r Value and (K) r +1)(ν min +1), the former being not smaller than the latter, but B being known from the recursion r A value of 85, not satisfying the transmission rate requirements of the system, K r The value is updated to K r -1; is namely K min The value of (c).
Step 22, T r Value T max Calculating the current diversity gain v ═ d o,r (T r ,K r ) Is 1; is not more than the set diversity gain lower limit v min Then, T is updated r Value of T r -ν，63；
Step 21, knowing the current B according to the recurrence relation r The value is 85, the requirement of the system on the transmission rate is not met, and the process is exited.
Step 22, updating the optimal combination of the block OFDM-IM system carrier
So far, the adaptive block OFDM-IM system ends the example process based on the maximized joint gain carrier selection scheme.
The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.
Claims (6)
1. A method for selecting OFDM-IM carrier activation is characterized in that a method for maximizing the selection of combined gain carrier is adopted to realize a self-adaptive block OFDM-IM system, the combined gain is a weighted product of system diversity gain and transmission rate, the weighted value omega belongs to [0,1],
the method comprises the following steps:
step 1, initializing a system, and setting an initial value of the system, wherein the initial value comprises an upper limit T of the total number of carriers max Giving the sub-block number G of the partitioned OFDM-IM system, and setting the lower limit B of the transmission rate of the system min Setting a lower limit v of the diversity gain of the system min Counting an initial count r to be 1;
step 2, initializing a sub-block r, and setting the initial activated carrier number K for the sub-block r r To 1, an initial maximum diversity gain v is set max Setting an initial value T of the number of carriers r Is T max /G；
Step 3, determining the upper bound Sup { K) of the number of the r activated carriers of the sub-block r }；
Step 4, calculating the transmission rate B of the current system r If said B is r Greater than B min Then returning to the current K r Value as minimum number of active carriers K min Otherwise, increment the K r Repeating step 4 to recalculate B r ；
Step 5, setting the K r Value of Sup { K r And calculating the diversity gain v of the current r sub-block r If the diversity gain v is r Greater than the system diversity gain lower limit v min Then returning to the current K r Value as maximum number of active carriers K max And executing step 7, otherwise executing step 6;
step 6, updating the current carrier number T r Value of T r -ν r If said T is r Not more than (K) r +1)(ν max +1), then said K is decremented r And returning to the step 5 to calculate the v r Otherwise, directly returning to the step 4 to calculate the v r ；
Step 7, setting the initial maximum diversity gain value v of the system max ＝ν min +1, setting the initial active carrier number K of the sub-block r r ＝K max ；
Step 8, calculating and updating the current transmission rate B r Calculating the current r sub-block diversity gain v r ；
Step 9, if the carrier number T is currently r Is greater than or equal to (K) r +1)(ν max +1) and the current said rate B r Greater than B min If yes, jumping to execute the step 11;
step 10, decreasing the initial activated carrier number K r If the number of the initial active carriers K r Greater than the minimum number of active carriers K min If yes, jumping back to the step 8, otherwise, jumping to the step 13;
step 11, judging the v r Whether greater than v min If not, updating the T r Value and said B r The value is counted and the step 8 is skipped;
step 12, updating the v according to the calculation result max Maximum joint gain U max And combinations [ T r ,K r ]；
Step 13, updating and storing the optimal carrier combination of the block OFDM-IM system 
Wherein
Is a vector [ T ] containing the number of carriers of each sub-block 1 ,T 2 ,…,T G ] T ，
Is a vector [ K ] containing the number of carriers of each sub-block 1 ,K 2 ,…,T G ] T And incrementing the value of sub-block r;
step 14, judging the relation between the current subblock r and the subblock number G, and returning to the step 2 if the subblock r is not larger than the subblock number G;
step 15, outputting the optimal combination of the carriers
2. The OFDM-IM carrier activation selection method of claim 1 wherein the initial maximum diversity gain v in step 2 max A number greater than 1.
3. The OFDM-IM carrier activation selection method of claim 1, wherein the Sup { K ] in step 3 r The calculation formula is as follows,
4. the OFDM-IM carrier activation selection method of claim 1, wherein B in step 4 is r Is calculated by the formula
5. The OFDM-IM carrier activation selection method of claim 1, wherein B in step 8 is the same as r Is calculated by the formula
6. The OFDM-IM carrier activation selection method of claim 1, wherein the T is updated in step 11 r Value, formula T r ＝T r -ν r (ii) a Updating the B r Value of the formula B r ＝B r -1。
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107317783A (en) * | 2017-07-03 | 2017-11-03 | 电子科技大学 | Self-adaptive modulation method for index modulation OFDM |
| CN107332799A (en) * | 2017-07-03 | 2017-11-07 | 电子科技大学 | Planisphere design method for index modulation ofdm system |
| CN109617603A (en) * | 2019-01-04 | 2019-04-12 | 清华大学 | Visible light communication mixing light-dimming method and device based on index modulation |
-
2019
- 2019-12-19 CN CN201911317766.1A patent/CN110995401B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107317783A (en) * | 2017-07-03 | 2017-11-03 | 电子科技大学 | Self-adaptive modulation method for index modulation OFDM |
| CN107332799A (en) * | 2017-07-03 | 2017-11-07 | 电子科技大学 | Planisphere design method for index modulation ofdm system |
| CN109617603A (en) * | 2019-01-04 | 2019-04-12 | 清华大学 | Visible light communication mixing light-dimming method and device based on index modulation |
Non-Patent Citations (3)
| Title |
|---|
| Enhanced Orthogonal Frequency-Division;Shuping Dang，Guoqing Ma，Basem Shihada，Mohamed-Slim Alouini;《IEEE》;20191031;P7907-P7915,左侧第二段 * |
| OFDM With Subcarrier Number Modulation;Ahmad M. Jaradat , Jehad M. Hamamreh , and Huseyin Ars;《IEEE》;20181231;全文 * |
| 融合通用滤波多载波的非正交多址接入技术*;赵金鑫，万海斌，黎相成，陈海强，覃团发;《电讯技术》;20190331;全文 * |
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