Rangefinder using expanded time delay

• US 4,297,701 A
• Filed: 08/08/1979
• Issued: 10/27/1981
• Est. Priority Date: 08/08/1979
• Status: Expired due to Term

• Current Assignee: John D. Angleman
• Original Assignee: John D. Angleman
• Inventors: Henriques, Lance
• Primary Examiner(s): Tubbesing, T. H.
• Application Number:
  US06/064,390
• Time in Patent Office: 811 Days
• Field of Search: 343/6.5 R, 343/6.5 LC, 343/6.8 R
• US Class Current: 342/42
• CPC Class Codes: A63B 2102/32 Golf
• CPC Class Codes: A63B 2220/13 Relative positions
• CPC Class Codes: A63B 57/00 Golfing accessories
• CPC Class Codes: G01S 13/78 discriminating between different kinds of targets, e.g. IFF-radar, i.e. identification of friend or foe G01S13/75, G01S13/79 take precedence
• CPC Class Codes: G01S 13/88 Radar or analogous systems specially adapted for specific applications electromagnetic prospecting or detecting of objects, e.g. near-field detection, G01V3/00
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence

Abstract

The system is comprised of a plurality of hand held units carried by golfers, a plurality of flagstick units located at a golf course and a master Clubhouse unit. Each hand held unit includes a power source, a transceiver, a distance determining circuit, a keyboard with display, an audio generator and a microprocessor which controls the mode of the hand held unit. Each flagstick unit is comprised of a power source, a transceiver and a controlling microprocessor. The microprocessor includes a plurality of subprograms which control the function of the hand held unit or the flagstick unit. To determine the distance between a hand held unit and a flagstick unit, a button on the keyboard is pressed to select a particular flagstick unit. The microprocessor is activated to activate the audio generator indicating the button was properly pressed and, simultaneously, the distance determining circuit and transceiver are activated. The distance determining circuit is actually a timing circuit which measures the amount of time required for the signal from the transceiver to reach the selected flagstick unit and be retransmitted by the flagstick unit back to the particular hand held unit. The distance determining circuit is actually a capacitor which is linearly charged during transmission time and discharged at a slower rate to determine the amount of charge which is directly proportional to the distance between the hand held unit and the flatstick unit. The hand held units are also provided with a magnetic charging circuit so that the unit can be charged without the use of connections and so that the unit can be embodied in a sealed apparatus.

Claims

1. A system for determining the distance between a first point and a second point comprising:

(a) first transceiver means located at the first point for transmitting a first signal burst on a given frequency and for receiving signals on the given frequency;

(b) second transceiver means located at the second point for receiving the first signal burst on the given frequency and for retransmitting a second signal burst on the given frequency in response to the first signal burst; and

(c) timing means for measuring the period of time between the transmission of the first signal burst by the first transceiver means and the receipt of the second signal burst by the second transceiver means, whereby the period of time is directly proportional to the distance between the first point and the second point, said timing means being comprised of an integrator including a capacitor, a means for linearly charging the capacitor at a charge rate during the period of time, a means for linearly discharging at a slower rate than said charge rate the capacitor after the period of time, a threshold detector for detecting when the state of charge of the capacitor reaches a predetermined value;

(d) and a microprocessor for measuring an amount of time that the capacitor is charged to a value of at least said predetermined value, the amount of time corresponding to said distance between the first point and the second point.

2. The system of claim 1 wherein said first transceiver means is a hand held unit comprising a radio means for transmitting the first signal burst and for receiving the second signal burst, a microprocessor for activating the timing means and the radio means, and a power source selectively connected through the microprocessor to the timing means and the radio means.

3. The system of claim 2 wherein said microprocessor analyzes the period of time by subtracting the period of delay from the time the second transceiver means receives the first signal burst to the time that the second transceiver means transmits the second signal burst and converts a signal corresponding to the resulting period of time into a signal corresponding to the distance between the first point and the second point;

and wherein a display means is provided for displaying the distance between the first point and the second point as represented by the corresponding resultant signal.

4. The system of claim 3 wherein the second transceiver means is comprised of a flagstick unit including a second power source, a second radio means for receiving the first signal and transmitting the second signal and a second microprocessor for controlling the second radio means.

6. The system of claims 4 or 5 further including a magnetic induction coil recharging means for recharging the power source of the hand held unit.

7. The system of claim 6 further including a solar recharging means for recharging the second power source of the flagstick unit.

5. A system for determining the distance between a first point and a second point comprising:

(a) a timing means

(b) first transceiver means located at the first point for transmitting a first signal burst on a given frequency and for receiving signals on the given frequency, the first transceiver means being a hand held unit comprising a radio means for transmitting the first signal burst and for receiving the second signal burst;

(c) a first microprocessor for activating the timing means, the transceiver and a power source, the power source being selectively connected through the first microprocessor to the timing means and radio means; and

(d) second transceiver means located at the second point for receiving the first signal burst on the given frequency and for retransmitting a second signal burst on the given frequency in response to the first signal burst, the second transceiver means being comprised of a flagstick unit including a second power source, a second radio means for receiving the first signal and transmitting the second signal, and a second microprocessor for controlling the second transceiver;

(e) wherein the timing means provides a delay signal between the transmission of the first signal burst by the first transceiver means and the receipt of the second signal burst by the first transceiver means by linearly charging a capacitor at a charge rate, detecting when the the state of charge of the capacitor achieves a predetermined value and linearly discharging the capacitor at a slower rate than said charge rate, whereby the delay signal is directly proportional to the distance between the first point and the second point;

(f) and wherein said first microprocessor analyzes the delay signal by subtracting the period of delay from the time the second transceiver means receives the first signal burst to the time that the second transceiver means transmits the second signal burst and converts a signal corresponding to the resulting period of time into a signal corresponding to the distance between the first point and the second point as represented by the corresponding resultant signal.