Title :
A design of 10-GHz delta-sigma modulator using a 4-level differential resonant-tunneling quantizer
Author :
Eguchi, Keisuke ; Chibashi, Masaru ; Waho, Takao
Author_Institution :
Dept. of Electr. & Electron. Eng., Sophia Univ., Tokyo, Japan
Abstract :
An ultrahigh-speed continuous-time delta-sigma modulator using a 4-level resonant-tunneling quantizer has been investigated. The quantizer consists of four resonant-tunneling diodes (RTDs) and a source-coupled high-electron-mobility transistor (HEMT) pair, and operates in the fully-differential mode. Circuit simulation shows that the present first-order delta-sigma modulator has a signal-to-noise ratio (SNR) of 49.4 dB at a sampling frequency of 10 GHz and an input bandwidth of 100 MHz. An improvement in the SNR by 5.6 dB is obtained by increasing the number of quantization level from two to four.
Keywords :
circuit simulation; delta-sigma modulation; high electron mobility transistors; quantisation (signal); resonant tunnelling diodes; 10-GHz delta-sigma modulator; 4-level differential resonant-tunneling quantizer; SNR; circuit simulation; resonant-tunneling diode; signal-to-noise ratio; source-coupled high-electron-mobility transistor pair; Bandwidth; Circuit simulation; Delta modulation; Diodes; Frequency; HEMTs; MODFETs; Resonant tunneling devices; Sampling methods; Signal to noise ratio;
Conference_Titel :
Multiple-Valued Logic, 2005. Proceedings. 35th International Symposium on
Print_ISBN :
0-7695-2336-6
DOI :
10.1109/ISMVL.2005.2
