例句與用法

1. Cvsd （ continuous variable slope delta modulation ） voice coding enables operation at high bit - error rates
   連續可變斜率增量調制的語音編碼可以在高誤碼率的情況下正常工作。
2. Reducing the bit - error rate in digital communication with error - correction technology and improving the quality of communication have been widely defined and used as the standard technology all over the world
   利用糾錯碼技術降低各類數字通信系統的誤碼率,提高通信質量,已經在世界上許多國家作為一門標準技術而廣泛采用。
3. Future mobile communications have to support the transmission of high rate data and multimedia applications in the radio spectrum , which is already extremely scarce . the basic idea of adaptive coded modulation is to maintain a constant throughput by varying the transmitted power level , symbol transmission rate , constellation size , coding rate or any combination of these parameters . thus , without sacrificing bit - error rate ( ber ) , these schemes provide high average spectral efficiency by transmitting at high speeds under favorable channel conditions , and reducing throughput as the channel degrades
   自適應編碼調制( adaptivecodedmodulation , acm )的基本思想是在不犧牲系統傳輸性能(比如ber )為代價的前提下,通過單獨改變發送功率、波特率、編碼方案、碼率、調制方式,或者是綜合改變前面所述的各種參數,在有利的信道條件下,獲得較大的吞吐量,當信道質量下將時,相應地降低傳輸速率,最終達到提高平均頻譜效率的目的。
4. In this paper , bit - error rate performance analyses are presented for coded and un - coded frequency hopping m - ary frequency - shift keyed systems under the condition of additive white gaussian noise ( awgn ) and partial band noise jamming and multitone jamming . the use of error - correct codes provide a way to improve the performance of frequency hopping system , particularly the use of reed - solomon code in a fh system under the condition of partial band noise jamming can greatly improve the performance of system . so we provide the way of coding and decoding of rs code in c language . in the end , we offer the simulation of the performance of time diversity fh / 2fsk system over partial band jamming noise channels
   第一章為緒論，敘述跳頻通信的發展趨勢，以及基本概念，第二章及第三章介紹提高抗部分頻帶干擾的前向糾錯碼reed - solomon碼的原理和實現方法。第四章研究跳頻通信系統在各種干擾條件下的性能。最后在第五章以fh mfsk系統為例，探討在部分頻帶干擾下的系統性能，并進行計算機仿真，仿真結果表明采用分集技術和各種編碼技術對于系統的性能改善具有明顯的效果。