CN112260976A - Broadband system anti-interference method based on F-OFDM modulation - Google Patents
Broadband system anti-interference method based on F-OFDM modulation Download PDFInfo
- Publication number
- CN112260976A CN112260976A CN202011110845.8A CN202011110845A CN112260976A CN 112260976 A CN112260976 A CN 112260976A CN 202011110845 A CN202011110845 A CN 202011110845A CN 112260976 A CN112260976 A CN 112260976A
- Authority
- CN
- China
- Prior art keywords
- sub
- data
- interference
- band
- entering
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- 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
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- 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
- H04L27/2626—Arrangements specific to the transmitter only
- H04L27/2627—Modulators
- H04L27/2634—Inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators in combination with other circuits for modulation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- 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
- H04L27/2647—Arrangements specific to the receiver only
- H04L27/2655—Synchronisation arrangements
- H04L27/2689—Link with other circuits, i.e. special connections between synchronisation arrangements and other circuits for achieving synchronisation
- H04L27/2691—Link with other circuits, i.e. special connections between synchronisation arrangements and other circuits for achieving synchronisation involving interference determination or cancellation
Abstract
The invention discloses an anti-interference method of a broadband system based on F-OFDM modulation, which comprises the following steps: 1) the initial sub-band number is 1, after the information source is coded, modulated and sub-carrier mapped, F-OFDM symbol modulation is carried out and framing is carried out to send out signals; 2) after the wireless signal is processed by a channel and FFT, interference detection is carried out on an idle frame time slot according to a designed multiframe structure, and the interference position is recorded; 3) replanning the frequency spectrum resource according to the interference position, dividing the number of sub-bands, and calculating the corresponding sub-band filter coefficient; 4) setting an interference region frequency domain window, and calculating EVM values inside and outside the window to serve as a basis for sub-band subcarrier spacing and data modulation mode adjustment; 5) adjusting the sending end according to the divided sub-bands and corresponding parameters, re-mapping sub-carriers according to the number of the sub-bands, framing and sending signals; 6) the receiving end analysis process combines the data analyzed by each sub-band and enters a decoding module for decoding; by systematic simulation under the same AWGN channel, the invention not only improves the communication reliability of the broadband system in a complex channel environment, but also solves the problem of low throughput of the broadband system under the condition of the same coding efficiency.
Description
Technical Field
The invention belongs to the technical field of wireless communication, and particularly relates to an anti-interference method for a broadband system based on F-OFDM modulation.
Background
Channel narrow-band interference and multipath frequency domain selective fading seriously affect the performance of a broadband wireless communication system, and a system lacking anti-interference measures even cannot work normally at all.
In order to effectively resist narrowband interference and fading influence in a system and comprehensively improve the communication reliability of the system in a complex channel environment, the interference position and strength are positioned through a special interference detection time slot and a detection algorithm, frequency resources planned by a data link layer are used, subcarriers of an interfered frequency band are deducted through information interaction between the link layer and a physical layer, interference frequency points are actively avoided, meanwhile, a variable subcarrier spacing method in an F-OFDM (Filtered OFDM) modulation method is utilized, the subcarrier spacing is reduced, the subcarrier load number is increased under the condition of not reducing the coding efficiency, and the throughput capacity of a broadband system in the data transmission process is ensured.
Disclosure of Invention
Based on the method, the invention aims to provide an anti-interference method of a broadband system based on F-OFDM modulation, and the broadband system adopting the method can still carry out normal data communication under single tone interference, multi-tone interference and broadband interference.
The invention is realized by the following technical scheme:
an anti-interference method of a broadband system based on F-OFDM modulation comprises the following steps:
step S1, initializing the number of the set sub-bands to 1, after the information source is coded, modulated and sub-carrier mapped, carrying out F-OFDM symbol modulation and framing to send out signals, and entering step S2;
step S2, after the wireless signal is processed by the channel and FFT, according to the designed multiframe structure, the interference detection is carried out on the idle time slot, the interference position is recorded, and the step S3 is entered;
step S3, replanning the frequency spectrum resource according to the calculated interference position, avoiding the interference frequency point, dividing the sub-band number, calculating the corresponding sub-band filter coefficient, setting the frequency domain window of the interference area, calculating the EVM value inside and outside the window as the basis of sub-band sub-carrier interval or data modulation mode adjustment, and entering step S4;
and step S4, adjusting the sending end and the receiving end by using the number of the divided sub-bands and corresponding calculation parameters, and merging the sub-band analyzed data blocks at the receiving end to complete the anti-interference signal processing of the broadband system.
Further, the multiframe structure design in step S2 is as follows, where every M + N subframes in the system are one multiframe, and include M data subframes and N idle subframes. The idle sub-frame is used for detecting environmental interference noise, the data sub-frame is used for system service transmission, and the sending time parameter of the data is restricted by defining a multi-frame structure so as to ensure the correct execution of sending and receiving;
further, the interference detection in step S2 includes the following steps:
step S21, performing FFT operation, and proceeding to step S22;
step S22, calculating the signal spectrum energy and normalizing the signal spectrum energy,
wherein, in the step (A),
is the peak energy of the frequency spectrum,
to the spectral average energy, the process proceeds to step S23;
step S23, setting interference energy threshold value
And compare if
Recording the location and energy of the disturbance
) Wherein, in the step (A),
is the RB subscript where the interference point is located,
is an interference point; if it is not
Judging whether the interference is avoided, and continuing to execute the next module;
further, the spectrum planning in step S3 includes the following steps:
step S31, setting a frequency domain window according to the interference position calculated by the interference detection,
proceeding to step S32;
step S32, calculating an error vector magnitude value (EVM) within the frequency domain window,
wherein, in the step (A),
in order to be able to determine the amplitude error,
to modulate data for the originating side, go to step S33;
step S33, judging the signal quality in the current range, if yes
If so, judging that the interference signal exists in the current window and is the subcarrier needing to be deleted, and entering the step S34; if it is not
Entering a demodulation module for demodulation;
step S34, replanning the deleted sub-carriers into
Each sub-band, and the filter coefficient of each sub-band is calculated at the same time, and the process goes to step S35;
step S35, calculating an error vector magnitude value (EVM) outside the frequency domain window,
wherein, in the step (A),
in order to be able to determine the amplitude error,
in order for the data to be modulated by the originating side,
for the ith subband, proceed to step S36;
step S36, judging whether the signal quality adjustment parameter in the current range guarantees the data throughput not to be reduced, if so, judging whether the signal quality adjustment parameter in the current range guarantees the data throughput not to be reduced or not
Adjusting the subcarrier spacing; if it is not
Then the modulation mode of the sub-band is increased, wherein
The threshold value is a high-order modulation mode, and the current signal state is fed back to the transmitting end modulation module;
further, the adjusting of the originating terminal and the receiving terminal in step S4 includes the following steps:
step S41, according to the number of sub-bands
For the modulated data, the number of the data blocks is divided into
If the adjustment is the subcarrier spacing adjustment, the process proceeds to step S42; if the data modulation mode is improved, the step S43 is executed;
step S42, according to the calculated sub-carrier interval of each sub-band, mapping sub-carrier data, carrying out F-OFDM symbol modulation, framing and transmission, and entering step S44;
step S43, improving the data modulation mode of the sub-band, mapping the sub-carrier data, carrying out F-OFDM symbol modulation, framing and transmission, and entering step S44;
step S44, the receiving end demodulates and combines the data of each sub-band
And the data blocks enter a decoding module for decoding to complete the anti-interference signal processing of the system.
Drawings
Fig. 1 is a signal processing flow diagram of a transmission system of the present invention;
fig. 2, a multiframe structure of a transmission system of the present invention;
FIG. 3 is a flow chart of the interference detection and spectrum planning process of the present invention;
fig. 4 shows the subband division process of the wideband system of the present invention.
Detailed Description
To make the objects and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings and examples.
Fig. 1 is a flow chart of signal processing of a transmission system according to the present invention, and the specific method includes the following steps:
step S11, initializing the setting of the number of sub-bands
After the information source is coded, modulated and sub-carrier mapped, F-OFDM symbol modulation is carried out and framing is carried out to send out signals, and the step S12 is carried out;
step S12, after the wireless signal is processed by the channel and FFT, according to the designed multiframe structure, as shown in fig. 2, M =99, N =1, T =1S, performing interference detection on the idle time slot, recording the interference position, and proceeding to step S13;
step S13, replanning the frequency spectrum resource according to the calculated interference position, avoiding the interference frequency point, dividing the sub-band number, calculating the corresponding sub-band filter coefficient, setting the frequency domain window of the interference area, calculating the EVM value inside and outside the window as the basis of sub-band sub-carrier interval or data modulation mode adjustment, and entering step S14;
and step S14, adjusting the sending end and the receiving end by using the number of the divided sub-bands and corresponding calculation parameters, and merging the sub-band analyzed data blocks at the receiving end to complete the anti-interference signal processing of the broadband system.
Fig. 3 is a flowchart of interference detection and spectrum planning processing of the present invention, and the specific method includes the following steps:
step S31, carrying out interference detection on the received signal to obtain an RB subscript where an interference position is located, and entering step S32;
step S32, setting a frequency domain window, nRB =2,
and calculating the EVM value in the frequency domain window, and setting the demodulation threshold value
Proceeding to step S33;
step S33, if the calculated EVM is greater than
Deleting the current frequency point subcarrier, and entering step S34; otherwise, directly entering a demodulation module for demodulation;
step S34, replanning the spectrum, dividing into 2 sub-bands as shown in fig. 4, calculating the filter coefficient of each sub-band, and proceeding to step S35;
step S35, calculating EVM value outside frequency domain window, setting threshold value of high-order modulation mode
Proceeding to step S36;
step S36, if greater than
If so, adjusting the subcarrier interval and carrying out F-OFDM symbol modulation; if less than
Increasing the modulation mode of the sub-band and carrying out F-OFDM symbol modulation; and simultaneously, the current signal state is fed back to the transmitting end modulation module to complete the signal processing process.
In summary, the above description is only a preferred example of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (5)
1. An anti-interference method of broadband system based on F-OFDM modulation is characterized in that the number of the initial sub-bands of a system transmitting end is set to be 1, data sub-carrier mapping is carried out, and framing is carried out to send out signals; the receiving end carries out interference detection on an idle frame time slot and records the interference position in the process of processing the received multi-frame data; re-planning the frequency spectrum resources according to the interference position, avoiding interference frequency points, dividing the number of sub-bands, and calculating corresponding sub-band filter coefficients; setting an interference region frequency domain window, and calculating EVM values inside and outside the window to serve as a basis for sub-band subcarrier spacing and data modulation mode adjustment; adjusting the transmitting end by utilizing the number of the divided sub-bands and corresponding calculation parameters, blocking the modulation data according to the number of the sub-bands, respectively carrying out sub-carrier mapping on different sub-bands and framing to send signals; and analyzing the data at the receiving end, combining the analyzed data of each sub-band, and entering a decoding module for decoding.
2. Multiframe data as in claim 1, wherein every M + N subframes in the system is a multiframe, comprising M data subframes and N idle subframes; the idle sub-frame is used for detecting the environmental interference noise, the data sub-frame is used for system service transmission, and the sending time parameter of the data is restricted by the definition of the multiframe structure so as to ensure the correct execution of the receiving and sending.
3. The interference detection according to claim 1, characterized in that the embodying step comprises,
3.1 executing FFT operation, and entering step 3.2;
3.2 calculating the signal spectrum energy and normalizing the signal spectrum energy,
wherein, in the step (A),
is the peak energy of the frequency spectrum,
entering step 3.3 for the spectrum mean energy;
3.3 setting an interference energy threshold value,
and compare if
Recording the location and energy of the disturbance
) Wherein, in the step (A),
is the RB subscript where the interference point is located,
is an interference point; if it is not
And judging whether the interference is avoided, and continuously executing the next module.
4. Spectral planning and sub-band partitioning according to claim 1, characterized in that the specific implementation steps comprise,
4.1 setting a frequency domain window according to the interference position calculated by the interference detection,
，
entering the step 4.2;
4.2 calculate the error vector magnitude value (EVM) within the frequency domain window,
wherein, in the step (A),
in order to be able to determine the amplitude error,
modulating data for the transmitting end, and entering the step 4.3;
4.3 judging the signal quality in the current range, if
If so, judging that the interference signal exists in the current window, and the subcarrier needs to be deleted, and entering the step 4.4; if it is not
Entering a demodulation module for demodulation;
4.4 replanning the deleted sub-carriers into sub-carriers
Calculating the filter coefficient of each sub-band simultaneously, and entering step4.5;
4.5 calculate the Error Vector Magnitude (EVM) outside the frequency domain window,
wherein, in the step (A),
in order to be able to determine the amplitude error,
in order for the data to be modulated by the originating side,
entering step 4.6 for the ith subband;
4.6 judging the signal quality adjusting parameter in the current range to ensure that the data throughput is not reduced, if so, judging whether the signal quality adjusting parameter in the current range is in the same range as the signal quality adjusting parameter in the current range or not
Adjusting the subcarrier spacing; if it is not
Then the modulation mode of the sub-band is increased, wherein
And the current signal state is fed back to the transmitting end modulation module at the same time when the current signal state is the threshold value of the high-order modulation mode.
5. The origination adaptation of claim 1, wherein the embodying step comprises,
5.1 the originating received signal state and processing, including the number of sub-bands
Spacing of subcarriers
The adjustment or modulation mode mcs is increased, the modulation data is divided into blocks, the number of the data blocks is
If the adjustment is the subcarrier spacing adjustment, the step 5.2 is carried out; if the data modulation mode is improved, entering step 5.3;
5.2, mapping the sub-carrier data according to the calculated sub-carrier interval of each sub-band, wherein the sub-band bandwidth is reduced, the modulation mode is unchanged, and the number of the sub-carriers is increased so as to ensure that the data transmission rate is unchanged, carrying out F-OFDM symbol modulation, framing and transmission, and entering step 5.4;
5.3, improving the data modulation mode of the sub-band, mapping the sub-carrier data, reducing the bandwidth, keeping the number of the sub-carriers unchanged, improving the modulation mode to ensure that the data transmission rate is unchanged, carrying out F-OFDM symbol modulation, framing and transmission, and entering the step 5.4;
5.4 the receiving end demodulates and combines the data of each sub-band
And the data blocks enter a decoding module for decoding to complete the anti-interference signal processing of the system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011110845.8A CN112260976B (en) | 2020-10-16 | 2020-10-16 | Broadband system anti-interference method based on F-OFDM modulation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011110845.8A CN112260976B (en) | 2020-10-16 | 2020-10-16 | Broadband system anti-interference method based on F-OFDM modulation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112260976A true CN112260976A (en) | 2021-01-22 |
| CN112260976B CN112260976B (en) | 2022-10-14 |
Family
ID=74244532
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011110845.8A Active CN112260976B (en) | 2020-10-16 | 2020-10-16 | Broadband system anti-interference method based on F-OFDM modulation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112260976B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113131969A (en) * | 2021-03-22 | 2021-07-16 | 中国人民解放军61035部队 | Self-adaptive transmission method and device for resisting aiming type interference |
| CN114726700A (en) * | 2022-04-22 | 2022-07-08 | 哈尔滨工业大学 | Interference scene-oriented multi-carrier communication system self-adaptive anti-interference synchronization method |
| CN116056221A (en) * | 2022-12-06 | 2023-05-02 | 深圳市极客空间科技有限公司 | Method and system for improving frequency domain resource allocation to realize application of LTE (Long term evolution) in Internet of things |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102427441A (en) * | 2011-12-09 | 2012-04-25 | 杭州宏睿通信技术有限公司 | Anti-interference method applied to time-division OFDM (Orthogonal Frequency Division Multiplexing) system |
| CN103036836A (en) * | 2011-10-10 | 2013-04-10 | 京信通信系统（中国）有限公司 | Orthogonal frequency division multiple access (OFDMA) system signal processing method and device |
| CN103095633A (en) * | 2011-11-04 | 2013-05-08 | 上海瀚讯无线技术有限公司 | Method resisting narrow-band interference in orthogonal frequency division multiplexing (OFDM) communication system |
| CN103581092A (en) * | 2012-08-08 | 2014-02-12 | 中国移动通信集团公司 | Method and device for reducing out-of-band interference of cognitive radio |
| JP2015027069A (en) * | 2013-07-29 | 2015-02-05 | エフシーアイ インク | Ofdm reception signal processing method and ofdm receiver using the same |
| WO2016039668A2 (en) * | 2014-09-08 | 2016-03-17 | Telefonaktiebolaget L M Ericsson (Publ) | Interference mitigation |
| CN110677186A (en) * | 2019-08-22 | 2020-01-10 | 西安空间无线电技术研究所 | Satellite communication anti-interference method based on carrier splitting |
| CN111698185A (en) * | 2020-06-16 | 2020-09-22 | Oppo广东移动通信有限公司 | Carrier interference elimination method and device, electronic equipment and storage medium |
| CN113794664A (en) * | 2021-09-10 | 2021-12-14 | 北京环佳通信技术有限公司 | Anti-interference method based on subcarrier deduction |
-
2020
- 2020-10-16 CN CN202011110845.8A patent/CN112260976B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103036836A (en) * | 2011-10-10 | 2013-04-10 | 京信通信系统（中国）有限公司 | Orthogonal frequency division multiple access (OFDMA) system signal processing method and device |
| CN103095633A (en) * | 2011-11-04 | 2013-05-08 | 上海瀚讯无线技术有限公司 | Method resisting narrow-band interference in orthogonal frequency division multiplexing (OFDM) communication system |
| CN102427441A (en) * | 2011-12-09 | 2012-04-25 | 杭州宏睿通信技术有限公司 | Anti-interference method applied to time-division OFDM (Orthogonal Frequency Division Multiplexing) system |
| CN103581092A (en) * | 2012-08-08 | 2014-02-12 | 中国移动通信集团公司 | Method and device for reducing out-of-band interference of cognitive radio |
| JP2015027069A (en) * | 2013-07-29 | 2015-02-05 | エフシーアイ インク | Ofdm reception signal processing method and ofdm receiver using the same |
| WO2016039668A2 (en) * | 2014-09-08 | 2016-03-17 | Telefonaktiebolaget L M Ericsson (Publ) | Interference mitigation |
| CN110677186A (en) * | 2019-08-22 | 2020-01-10 | 西安空间无线电技术研究所 | Satellite communication anti-interference method based on carrier splitting |
| CN111698185A (en) * | 2020-06-16 | 2020-09-22 | Oppo广东移动通信有限公司 | Carrier interference elimination method and device, electronic equipment and storage medium |
| CN113794664A (en) * | 2021-09-10 | 2021-12-14 | 北京环佳通信技术有限公司 | Anti-interference method based on subcarrier deduction |
Non-Patent Citations (3)
| Title |
|---|
| QINGHUA SHI: "Fractionally Spaced Frequency-Domain MMSE Receiver for OFDM Systems", 《IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY》 * |
| YOU-WEI CHEN: "A Reliable OFDM-Based MMW Mobile Fronthaul With DSP-Aided Sub-Band Spreading and Time-Confined Windowing", 《JOURNAL OF LIGHTWAVE TECHNOLOGY》 * |
| 马涛: "OFDM系统干扰消除方法研究", 《中国优秀硕士学位论文全文数据库 (信息科技辑)》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113131969A (en) * | 2021-03-22 | 2021-07-16 | 中国人民解放军61035部队 | Self-adaptive transmission method and device for resisting aiming type interference |
| CN114726700A (en) * | 2022-04-22 | 2022-07-08 | 哈尔滨工业大学 | Interference scene-oriented multi-carrier communication system self-adaptive anti-interference synchronization method |
| CN114726700B (en) * | 2022-04-22 | 2024-02-06 | 哈尔滨工业大学 | Self-adaptive anti-interference synchronization method of multi-carrier communication system facing interference scene |
| CN116056221A (en) * | 2022-12-06 | 2023-05-02 | 深圳市极客空间科技有限公司 | Method and system for improving frequency domain resource allocation to realize application of LTE (Long term evolution) in Internet of things |
| CN116056221B (en) * | 2022-12-06 | 2024-03-22 | 深圳市极客空间科技有限公司 | Method and system for improving frequency domain resource allocation to realize application of LTE (Long term evolution) in Internet of things |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112260976B (en) | 2022-10-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112260976B (en) | Broadband system anti-interference method based on F-OFDM modulation | |
| US7308052B2 (en) | Radio transmitter apparatus and modulation scheme selecting method | |
| US7852814B2 (en) | Transmission control frame generation device and transmission control device | |
| US8811504B2 (en) | Method of determining a channel quality and modem | |
| EP2074706B1 (en) | Transmit power control based on path loss estimation | |
| US20180019774A1 (en) | Method for frequency- and time-selective interference suppression for a communication system based on ofdm, and receiver therefor | |
| US8804861B2 (en) | Peak-to-average power ratio reduction in a multicarrier signal | |
| US7548522B2 (en) | Orthogonal frequency division multiplexing wireless communication operable on frequency selective channel, and channel compensation method | |
| US20090034407A1 (en) | Receiver-site restoration of clipped signal peaks | |
| US10270634B2 (en) | Signal transmission apparatus and multicarrier communication system | |
| EP1924045B1 (en) | OFDM with bandwidth limitation | |
| Rajbanshi | OFDM-based cognitive radio for DSA networks | |
| US8295413B2 (en) | Doppler frequency estimating device, receiving device, recording medium and Doppler frequency estimating method | |
| CN101986629B (en) | Method and device for estimating narrowband interference as well as receiving equipment thereof | |
| US20210367815A1 (en) | Inter-carrier interference compensation | |
| CN117424659A (en) | Anti-interference method for 5G broadband communication system | |
| KR100542114B1 (en) | Wireless wireless communication system based on the orthogonal frequency division multiplexing and method for channel compensation | |
| CN111277245B (en) | Design method for low-order sub-band filter of filtering orthogonal frequency division multiplexing system | |
| Ho et al. | A novel combined PAPR reduction and channel estimation approach for OFDM systems | |
| US20080159434A1 (en) | Method of efficient techniques in an orthogonal frequency division multiplexing system with channel evaluation | |
| Xu et al. | Spectrum sidelobe suppression for discrete Fourier transformation-based orthogonal frequency division multiplexing using adjacent subcarriers correlative coding | |
| EP4300832A1 (en) | Wireless communication methods and devices for narrowband interference management | |
| US11824700B2 (en) | Systems and methods for peak-to-average power ratio (PAPR) reduction in OFDM signals | |
| Saci et al. | Cross-layer spectral efficiency of adaptive communications systems with QoS constraints | |
| Bartoli et al. | A novel mitigation scheme for JTIDS impulsive interference on LDACS system based on sensing and symbol retransmission |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |