Antenna director and method therefor

A VHF antenna (30) having at least one improved director (10) mounted to the boom (20) of said antenna (30) said improved director comprising:

• a first insulator (200) mounted to said boom (20),
• a first element (220) connected to said first insulator (200), said first element (220) having two half sections (222, 224) with the inboard end (240) of each half section being connected to said first insulator (200), the aforesaid ends (240) being separated from each other on said first insulator (200), each of said half sections (222, 224) of said first element (220) having an electrical length of substantially one-half wavelength at a frequency in the high end of the VHF band,
• a second insulator (200) mounted to said boom (20),
• a second element (210) connected to said second insulator (200), said second element (210) having an electrical length of substantially one-half wavelength at a frequency in the high end of the VHF band, said second element (210) having two half sections (212, 214) with the inboard end (240) of each half section being connected to said second insulator (200), the aforesaid ends (240) being separated from each other on said second insulator (200),
• a pair of opposing phasing lines (230) parallel to the longitudinal length of said boom (20) and separated from each other and located near said boom (20), each phasing line (230) electrically interconnecting said inboard ends (240) of said first and second element half sections located on the same side of said boom (20), said phasing lines (230) providing sufficient tuning between said first and second elements (210 and 220) to effectuate so resonating currents (I.sub.1, I.sub.2 and I.sub.3) in the first half section (222) of said first element (220), the second half section (224) of said first element (220), and in said second element (210) that are substantially in phase and additive.

An antenna (30) having a plurality of improved directors (10) mounted to the boom (20) of said antenna (30), each of said improved directors (10) comprising:

• a first element (220), said first element (220) having two symmetrical half sections (222, 224) with the inboard ends (240) of each aforesaid half section mounted (200) to and insulated from each other and from said boom (20), each of said half sections (222, 224) of said first element having an electrical length of substantially one-half wavelength at a desired frequency,
• a second element (210), said second element (210) having two symmetrical half sections (212, 214) with the inboard ends (240) of each aforesaid half section mounted to and insulated (200) from each other and from said boom (20), said second element (210) having an electrical length of substantially one-half wavelength at said desired frequency,
• means (230) on opposing sides of said boom (20) for interconnecting the inboard ends (240) of said first and second element symmetrical half sections (212 and 222, 214 and 224) located on opposing sides of the boom (20) to provide sufficient tuning between the opposing interconnected symmetrical first and second element half sections to effectuate a high impedance between the half sections (222, 224) of said first element (220) and produce half wavelength resonating currents (I.sub.1 and I.sub.2) in each half section and to further effectuate a low impedance between the half sections (212, 214) of said second element (210) and produce a half wavelength resonating current (I.sub.3), said currents (I.sub.1, I.sub.2, and I.sub.3) being substantially in phase and additive.

An improved director (10) mounted to the boom (20) of a VHF antenna (30), said improved director (10) being capable of increasing the gain of said antenna (30), said improved director (10) comprising:

• a first element (220), said first element (220) having two symmetrical half sections (222, 224) with the inboard ends (240) of each aforesaid half section mounted to (200) and insulated from each other and from said boom (20), said first element (220) being of sufficient length to half-wavelength resonate in the high end of the low VHF band, each half section (222, 224) being of sufficient length to half wavelength resonate in the high VHF band,
• a second element (210), said second element (210) having two symmetrical half sections (212, 214) with the inboard ends (240) of each aforesaid half section mounted to (200) and insulated from each other and from said boom (20), said second element (210) being of sufficient length to resonate only in the high VHF band, and
• means (230) on opposing sides of said boom (20) for interconnecting the inboard ends (240) of said first and second element symmetrical half sections (212 and 222, 214 and 224) located on opposing sides of the boom (20) and for providing sufficient tuning between the opposing interconnected symmetrical first and second element half sections to effectuate, in the high VHF band, (a) a high impedance between the half sections 222, 224) of said first element (220) and produce half wavelength resonating currents (I.sub.1 and I.sub.2) in each aforesaid half section and (b) a low impedance between the half sections (212, 214) of said second element (210) and produce a half wavelength resonating current (I.sub.3) across said second element (210) wherein all of said currents (I.sub.1, I.sub.2 and I.sub.3) are in phase and substantially additive, said tuning further effectuating, in the low VHF band a low impedance between the half sections (222, 224) of said first element (220) and producing a half wavelength resonating current (I.sub.4) across said first element (220).

A method for directing electromagnetic signals (800) in the high VHF band on a VHF antenna (30) to improve the gain of said antenna (30), said method comprising the steps of:

• resonanting a first element (220) having two half sections (222, 224) separated by insulators (200) in said high VHF band to provide a first current signal (I.sub.1) in the first half section (222) and a second current signal (I.sub.2) in the second half section (224),
• resonating a second element (210) having two half sections (212, 214) separated by insulators (200) in said high VHF band to provide a third current signal (I.sub.3),
• providing sufficiently high impedance between the opposing inboard ends (240) of the half sections (222 and 224) across said insulator (200) of said first element (210) so that each half section (222, 224) separately resonates in phase with each other, and
• providing sufficiently low impedance between the opposing inboard ends (240) across said insulator (200) of the half sections (212 and 214) to that said second element (210) resonates in phase with said first element.

A method for directing electromagnetic signals in the high VHF band (800) and in the high end of the low VHF band (900) of a VHF antenna (30), said method comprising the steps of:

• resonating a first element (220) having two physically and electrically separated half sections (222, 224) in the high VHF band (800) to provide a first current signal (I.sub.1) in the first half section (222) and a second current signal (I.sub.2) in the second half section (224),
• resonating a second element (210) having two physically and electrically separated half sections (212, 214) in the high VHF band (800) to provide a third current signal (I.sub.3) across said second element (210), said first, second, and third current signals being in phase with each other,
• reflecting a sufficiently high impedance to the region between the opposing inboard ends (240) of the half sections (222 and 224) of the first element when the signals in the high VHF band (800) encounters a first open stub (BCD B'C'D') formed by (a) the opposing physical and electrical connection between the inboard ends (240) of the first element (220) and the inboard ends (240) of the second element (210) and (b) the second element (210),
• reflecting a sufficiently low impedance to the region between the opposing inboard ends (240) of the half sections (212, 214) of the second element (210) when the signals in the high VHF band (800) encounter a second open stub (CBA, C'B'A') formed by (a) the opposing physical and electrical connection between the inboard ends (240) of the first element (220) and the inboard ends of the second element (210) and (b) the first element (220),
• resonating said first element (220) in the high end of the low VHF band (900) to provide a fourth current signal (I.sub.y) across said first element (220), and
• reflecting a sufficiently low impedance to the region between the opposing inboard ends (240) of the half sections (222, 224) of the first element when the signals in the high end of the low VHF band (900) encounter the first open stub (BCD, B'C'D').