Beam-hopping technology has become one of the major research hotspots for satellite communication in order to enhance their communication capacity and flexibility.However,beam hopping causes the traditional continuous...Beam-hopping technology has become one of the major research hotspots for satellite communication in order to enhance their communication capacity and flexibility.However,beam hopping causes the traditional continuous time-division multiplexing signal in the forward downlink to become a burst signal,satellite terminal receivers need to solve multiple key issues such as burst signal rapid synchronization and high-per-formance reception.Firstly,this paper analyzes the key issues of burst communication for traffic signals in beam hopping sys-tems,and then compares and studies typical carrier synchro-nization algorithms for burst signals.Secondly,combining the requirements of beam-hopping communication systems for effi-cient burst and low signal-to-noise ratio reception of downlink signals in forward links,a decoding assisted bidirectional vari-able parameter iterative carrier synchronization technique is pro-posed,which introduces the idea of iterative processing into car-rier synchronization.Aiming at the technical characteristics of communication signal carrier synchronization,a new technical approach of bidirectional variable parameter iteration is adopted,breaking through the traditional understanding that loop struc-tures cannot adapt to low signal-to-noise ratio burst demodula-tion.Finally,combining the DVB-S2X standard physical layer frame format used in high throughput satellite communication systems,the research and performance simulation are con-ducted.The results show that the new technology proposed in this paper can significantly shorten the carrier synchronization time of burst signals,achieve fast synchronization of low signal-to-noise ratio burst signals,and have the unique advantage of flexible and adjustable parameters.展开更多
The significance of cultural awareness in foreign language learning is an issue that earns hot discussion in the both fields of linguistics and instructional science. Being different from others, the observing angle i...The significance of cultural awareness in foreign language learning is an issue that earns hot discussion in the both fields of linguistics and instructional science. Being different from others, the observing angle in this paper lies in how the signal is processed. The four skills of listening, speaking, reading and writing are classified, by ways of signal processing, into two categorizes, namely receptive skills to which listening and reading belong, and productive skills to which speaking and writing belong. By analyzing the signal processing progress occurred in each of the four skills, the author is to argue the functions of cultural awareness in each of these four skills, in order to reinforce the importance of emphasizing cultural awareness in the new standards for English in China.展开更多
vips who have experienced Huawei’s vehicle reception service often Leave with a deep impression of the drivers,who are neatly dressed,courteous,and drive smoothly.Every detail of the reception process Leaves vips...vips who have experienced Huawei’s vehicle reception service often Leave with a deep impression of the drivers,who are neatly dressed,courteous,and drive smoothly.Every detail of the reception process Leaves vips feeling at ease.Chino Ouolity Doily once published a report about Huawei’s drivers,stating:"Being able to treat small matters according to the standards of big matters is the embodiment of Huawei's unique attention to detail.展开更多
基金This work was supported by the Key Research and Development Program of Shaanxi(2022ZDLGY05-08)the Application Innovation Program of CASC(China Aerospace Science and Technology Corporation)(6230107001)+2 种基金the Research Project on Civil Aerospace Technology(D040304)the Research Project of CAST(Y23-WYHXJS-07)the Research Foundation of the Key Laboratory of Spaceborne Information Intelligent Interpretation(2022-ZZKY-JJ-20-01).
文摘Beam-hopping technology has become one of the major research hotspots for satellite communication in order to enhance their communication capacity and flexibility.However,beam hopping causes the traditional continuous time-division multiplexing signal in the forward downlink to become a burst signal,satellite terminal receivers need to solve multiple key issues such as burst signal rapid synchronization and high-per-formance reception.Firstly,this paper analyzes the key issues of burst communication for traffic signals in beam hopping sys-tems,and then compares and studies typical carrier synchro-nization algorithms for burst signals.Secondly,combining the requirements of beam-hopping communication systems for effi-cient burst and low signal-to-noise ratio reception of downlink signals in forward links,a decoding assisted bidirectional vari-able parameter iterative carrier synchronization technique is pro-posed,which introduces the idea of iterative processing into car-rier synchronization.Aiming at the technical characteristics of communication signal carrier synchronization,a new technical approach of bidirectional variable parameter iteration is adopted,breaking through the traditional understanding that loop struc-tures cannot adapt to low signal-to-noise ratio burst demodula-tion.Finally,combining the DVB-S2X standard physical layer frame format used in high throughput satellite communication systems,the research and performance simulation are con-ducted.The results show that the new technology proposed in this paper can significantly shorten the carrier synchronization time of burst signals,achieve fast synchronization of low signal-to-noise ratio burst signals,and have the unique advantage of flexible and adjustable parameters.
文摘The significance of cultural awareness in foreign language learning is an issue that earns hot discussion in the both fields of linguistics and instructional science. Being different from others, the observing angle in this paper lies in how the signal is processed. The four skills of listening, speaking, reading and writing are classified, by ways of signal processing, into two categorizes, namely receptive skills to which listening and reading belong, and productive skills to which speaking and writing belong. By analyzing the signal processing progress occurred in each of the four skills, the author is to argue the functions of cultural awareness in each of these four skills, in order to reinforce the importance of emphasizing cultural awareness in the new standards for English in China.
文摘vips who have experienced Huawei’s vehicle reception service often Leave with a deep impression of the drivers,who are neatly dressed,courteous,and drive smoothly.Every detail of the reception process Leaves vips feeling at ease.Chino Ouolity Doily once published a report about Huawei’s drivers,stating:"Being able to treat small matters according to the standards of big matters is the embodiment of Huawei's unique attention to detail.
