| dc.contributor | IEEE | en_US |
| dc.creator (作者) | Guo Yifeng;Kuo Guomei;郭更生 | en_US |
| dc.date (日期) | 2007-04 | en_US |
| dc.date.accessioned | 14-Jan-2009 16:39:20 (UTC+8) | - |
| dc.date.available | 14-Jan-2009 16:39:20 (UTC+8) | - |
| dc.date.issued (上傳時間) | 14-Jan-2009 16:39:20 (UTC+8) | - |
| dc.identifier.uri (URI) | https://nccur.lib.nccu.edu.tw/handle/140.119/24855 | - |
| dc.description.abstract (摘要) | Adaptive multi-rate (AMR) codec can adaptively select one of eight modes according to the channel condition or the system load. AMR allows making a trade-off between voice capacity and the voice quality. In GSM networks, when the channel condition is worse than the threshold, the voice quality is unacceptable even using the lowest rate mode (4.75 kbps). In this paper, by compressing the AMR frame, a new defined lower bit rate AMR mode with 3.95 kbps is proposed to guarantee the voice quality in this case. The proposed mode is completely compatible with the specified AMR codec in standard. Moreover, this mode can be adopted in WCDMA networks. Compared with 12.2 kbps mode, this new one can increase the capacity by 135% and increase the coverage gain by 2.6 dB. | - |
| dc.format | application/ | en_US |
| dc.language | en | en_US |
| dc.language | en-US | en_US |
| dc.language.iso | en_US | - |
| dc.relation (關聯) | 2007-Spring IEEE Vehicular Technology Conference | en_US |
| dc.title (題名) | A New Defined Lower Bit Rate AMR Mode in GSM and WCDMA Networks | en_US |
| dc.type (資料類型) | conference | en |
| dc.identifier.doi (DOI) | 10.1109/VETECS.2007.159 | en_US |
| dc.doi.uri (DOI) | http://dx.doi.org/10.1109/VETECS.2007.159 | en_US |
