翻訳と辞書 Words near each other ・ Signal Zero ・ Signal – The Southeast Electronic Music Festival ・ Signal, Arizona ・ Signal, International Review of Signalist Research ・ Signal-averaged electrocardiogram ・ Signal-flow graph ・ Signal-recognition-particle GTPase ・ Signal-regulatory protein ・ Signal-regulatory protein alpha ・ Signal-to-crosstalk ratio ・ Signal-to-interference ratio ・ Signal-to-interference-plus-noise ratio ・ Signal-to-noise ratio ・ Signal-to-noise ratio (imaging) ・ Signal-to-noise statistic ・ Signal-to-quantization-noise ratio ・ Signal/One ・ Signalberg ・ Signalberg (Damme) ・ SignalDemand ・ Signale für die musikalische Welt ・ Signalen ・ Signalgrass ・ Signalhorn ・ Signalhorn (Silvretta Alps) ・ Signaling (telecommunications) ・ Signaling Compression ・ Signaling End Point ・ Signaling game ・ Signaling gateway Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Signal-to-quantization-noise ratio ： ウィキペディア英語版 Signal-to-quantization-noise ratio Signal-to-Quantization-Noise Ratio (SQNR or SNqR) is widely used quality measure in analysing digitizing schemes such as PCM (pulse code modulation) and multimedia codecs. The SQNR reflects the relationship between the maximum nominal signal strength and the quantization error (also known as quantization noise) introduced in the analog-to-digital conversion. The SQNR formula is derived from the general SNR (Signal-to-Noise Ratio) formula for the binary pulse-code modulated communication channel: :$\backslash mathrm=\backslash frac\; -\; 1)\}\; \backslash frac$ where :$P\_e$ is the probability of received bit error :$m\_p(t)$ is the peak message signal level :$m\_m(t)$ is the mean message signal level As SQNR applies to quantized signals, the formulae for SQNR refer to discrete-time digital signals. Instead of $m(t)$, we will use the digitized signal $x(n)$. For $N$ quantization steps, each sample, $x$ requires $\backslash nu=\backslash log\_2\; N$ bits. The probability distribution function (pdf) representing the distribution of values in $x$ and can be denoted as $f(x)$. The maximum magnitude value of any $x$ is denoted by $x\_$. As SQNR, like SNR, is a ratio of signal power to some noise power, it can be calculated as: :$\backslash mathrm\; =\; \backslash frac\}\; =\; \backslash frac^2">)\}$ The signal power is: :$\backslash overline\; =\; E()\; =\; P\_=\backslash int\_^2"\; TITLE="\backslash tilde^2">)\; =\; \backslash frac$ Giving: :$\backslash mathrm\; =\; \backslash frac^2\}$ When the SQNR is desired in terms of Decibels (dB), a useful approximation to SQNR is: :$\backslash mathrm|\_=P\_+6\backslash nu+4.8$ where $\backslash nu$ is the number of bits in a quantized sample, and $P\_$ is the signal power calculated above. Note that for each bit added to a sample, the SQNR goes up by approximately 6dB ($20\backslash times\; log\_(2)$). == References == * B.P.Li, Modern Digital and Analog Communication Systems (3rd edition), Oxford University Press, 1998 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Signal-to-quantization-noise ratio」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.