发明名称 |
Differential detecting device |
摘要 |
A signal adding device and a differential signal detecting device, wherein the signal adding device adds n input signals using n A/D converters, a selector and a lowpass filter. The n input signals are sampled in sequence by the A/D converter and digitized. Each digitized data is time-division multiplexed by the selector and input to the lowpass filter. The output of the lowpass filter is equal to an added signal of n input signals. The differential signal detecting device detects from inphase and quadrature-phase baseband signals the sine and cosine components of a phase difference at two instants of the phase-modulated signal. Two A/D converters digitize and convert the inphase and quadrature-phase baseband signals to inphase data and quadrature-phase data at predetermined intervals. A cosine component calculating unit calculates the cosine component by alternately selecting the inphase data and the quadrature-phase data. Similarly, a sine component calculating unit calculates the sine component by alternately selecting the inphase data and the quadrature-phase data. Two selectors select either the inphase data or the quadrature-phase data at predetermined intervals. By alternately selecting the inphase data and quadrature-phase data, and then multiplying the results, differential detection can be achieved with fewer multipliers and adders than the prior art differential detecting devices.
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申请公布号 |
US5712879(A) |
申请公布日期 |
1998.01.27 |
申请号 |
US19950506321 |
申请日期 |
1995.07.24 |
申请人 |
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD |
发明人 |
TATSUTA, AKIHIRO;URABE, YOSHIO;TAKAI, HITOSHI |
分类号 |
H04L27/227;H03D3/00;(IPC1-7):H04L27/22;H04L27/06 |
主分类号 |
H04L27/227 |
代理机构 |
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地址 |
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