Signal traits are often linked with the physiological state and behavior of their bearer. Direct examination of the causal links among these variables has provided substantial insight into the information content of s...Signal traits are often linked with the physiological state and behavior of their bearer. Direct examination of the causal links among these variables has provided substantial insight into the information content of signals, and into the costs and benefits of signal expression. Yet recent empirical work suggests that the social context in which signals are developed and displayed can play a major role not only in how signals are received, but also in coordinating and mediating the signaling phenotype itself. Here we review both well-established and emerging evidence for direct feedbacks among an individual＇s physiological state, be- havior, and signal elaboration. We then describe an integrative view of signaling that takes into account the bidirectional rela- tionships among components of phenotype and the social context in which signals are developed and displayed. Integrating dy- namic feedback between context and phenotype within models of the evolution and maintenance of signals may yield insights into how signals evolve, how signaling phenotypes are coordinated and maintained on ecological and evolutionary time scales, and how static signals continue to convey relevant phenotypic information about their bearer through time.展开更多
A microwave photonic link （MPL） with high spurious-free dynamic range （SFDR） is proposed and analyzed. The optical carrier is divided equally into two paths. The path I is modulated by radio frequency （RF） signa...A microwave photonic link （MPL） with high spurious-free dynamic range （SFDR） is proposed and analyzed. The optical carrier is divided equally into two paths. The path I is modulated by radio frequency （RF） signals in a Mach-Zehnder modulator （MZM）, and the phase of path 2 is controlled before the combination with path 1. By properly adjusting the phase difference of the two paths with the optical phase shifter, the third-order intermodulation distortion （IMD3） can be significantly suppressed. A proof-of-concept simulation is carried out. The results show that a reduction of 40 dB in the IMD3 and an improvement of 21.1 dB in the SFDR are achieved as compared with the conventional MZM-based MPL. The proposed MPL shows the advantages of simple structure, low cost and high efficiency.展开更多
基金Acknowledgements During the span of this project our work was funded by the National Science Foundation （DEBCAREER 1149942 to RJS）, and the National Evolutionary Synthesis Center （NSF #EF- 4120905606） through a graduate fellowship for DMZ.
文摘Signal traits are often linked with the physiological state and behavior of their bearer. Direct examination of the causal links among these variables has provided substantial insight into the information content of signals, and into the costs and benefits of signal expression. Yet recent empirical work suggests that the social context in which signals are developed and displayed can play a major role not only in how signals are received, but also in coordinating and mediating the signaling phenotype itself. Here we review both well-established and emerging evidence for direct feedbacks among an individual＇s physiological state, be- havior, and signal elaboration. We then describe an integrative view of signaling that takes into account the bidirectional rela- tionships among components of phenotype and the social context in which signals are developed and displayed. Integrating dy- namic feedback between context and phenotype within models of the evolution and maintenance of signals may yield insights into how signals evolve, how signaling phenotypes are coordinated and maintained on ecological and evolutionary time scales, and how static signals continue to convey relevant phenotypic information about their bearer through time.
基金supported by the Fundamental Research Funds for the Central Universities(No.JB142001-9)the Programme of Introducing Talents of Discipline to Universities China 111 Project(No.B08038)
文摘A microwave photonic link （MPL） with high spurious-free dynamic range （SFDR） is proposed and analyzed. The optical carrier is divided equally into two paths. The path I is modulated by radio frequency （RF） signals in a Mach-Zehnder modulator （MZM）, and the phase of path 2 is controlled before the combination with path 1. By properly adjusting the phase difference of the two paths with the optical phase shifter, the third-order intermodulation distortion （IMD3） can be significantly suppressed. A proof-of-concept simulation is carried out. The results show that a reduction of 40 dB in the IMD3 and an improvement of 21.1 dB in the SFDR are achieved as compared with the conventional MZM-based MPL. The proposed MPL shows the advantages of simple structure, low cost and high efficiency.
