发明名称 |
PROGRAMMABLE DIGITAL TONE DETECTOR |
摘要 |
<p>PROGRAMMABLE DIGITAL TONE DETECTOR A plurality of up/down counters are controlled by a programmed digital reference signal. The combination of a high select signal and a high input signal causes any one of the counters to increment (up) by one count while a combination of a high select signal and a low input signal causes any one of the counters to decrement (down) one count. A threshold detector signals an output when a specific combination of the counters reaches a predetermined combination count signifying correlation of the programmed reference with the input tone over a predetermined number of cycles. The phase of the input may be determined by noting which of the counters reaches the predetermined threshold.</p> |
申请公布号 |
CA1126865(A) |
申请公布日期 |
1982.06.29 |
申请号 |
CA19790332985 |
申请日期 |
1979.08.01 |
申请人 |
MOTOROLA, INC. |
发明人 |
BACKOF, CHARLES A., JR.;ROBINS, DAVID S. |
分类号 |
H04L27/14;G01R23/167;G01R25/00;H03H17/00;H03K9/04;H04L27/00;H04L27/26;H04Q1/457;(IPC1-7):04Q9/10 |
主分类号 |
H04L27/14 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|