Narrow-Band LPDA-A-DT V2 Narrow-Band Digitally Tuned LPDA Antenna

Product Overview

Key Features

• Digitally tuned filtering in DT Mode
• Narrow RF Bandwidth for maximum out-of-band signal rejection
• 24MHz or 48MHz Bandwidth available to order
• Wide-Band filtering in WB Mode – Fixed Bandwidth Mode
• No DC – Passive Mode with in-built Band-Pass filtering
• Extremely high dynamic range RF amplifier
• DT-Mode Tuning range 470-702MHz with 24MHz Bandwidth
• DT-Mode Tuning range 470-710MHz with 48MHz Bandwidth
• Tuning step 8MHz for 24MHz BW and 12MHz for 48MHz BW
• Independently user-adjustable input Attenuator and Booster gain adjustment
• Intuitive OLED display menu
• Powered through coax cable
• Integrated mount adaptor
• CNC-machined custom design

24MHz Bandwidth Digitally Tuned Frequency Table (470-702MHz)

BAND No:	FREQUENCY RANGE:	BAND No:	FREQUENCY RANGE:	BAND No:	FREQUENCY RANGE:
1	470-494 MHz	11	550-574 MHz	21	630-654 MHz
2	478-502 MHz	12	558-582 MHz	22	638-662 MHz
3	486-510 MHz	13	566-590 MHz	23	646-670 MHz
4	494-518 MHz	14	574-598 MHz	24	654-678 MHz
5	502-526 MHz	15	582-606 MHz	25	662-686 MHz
6	510-534 MHz	16	590-614 MHz	26	670-694 MHz
7	518-542MHz	17	598-622 MHz	27	678-702 MHz
8	526-550 MHz	18	606-630 MHz
9	534-558 MHz	19	614-638 MHz
10	542-566 MHz	20	622-646 MHz

48MHz Bandwidth Digitally Tuned Frequency Table (470-710MHz)

BAND No:	FREQUENCY RANGE:	BAND No:	FREQUENCY RANGE:	BAND No:	FREQUENCY RANGE:
1	470-518 MHz	7	542-590 MHz	13	614-662 MHz
2	482-530 MHz	8	554-602 MHz	14	626-674 MHz
3	494-542 MHz	9	566-614 MHz	15	638-686 MHz
4	506-554 MHz	10	578-626 MHz	16	650-698 MHz
5	518-566 MHz	11	590-638MHz	17	662-710 MHz
6	530-578 MHz	12	602-650 MHz

LPDA-A-DT V2 Antenna

Features and Operational Modes

Overview

The LPDA-A-DT V2 Digitally Tuned LPDA antenna is designed for operation within the 470-710MHz tuning range.

It consists of two components:

• The LPDA-P passive antenna section
• The Antenna Booster Module: a narrow-band tunable band-pass filter.

Tuneable Radio Frequency Filters:

Tunable Radio Frequency (RF) filters are essential components in managing crowded spectrum environments. These filters enable dynamic frequency selectivity, facilitating efficient spectrum management while rejecting unwanted RF signals and interference. They work by allowing specific frequency bands to pass through while attenuating undesired signals.

Advantages of Tunable RF Filtered LPDA Antennas

Unlike fixed-bandwidth filtered Log-Periodic Dipole Array (LPDA) antennas, which are limited to a specific frequency range, tunable RF filtered LPDA antennas offer greater flexibility by allowing operation across multiple frequency bands. The LPDA-A-DT V2 is a tunable filter design that operates from 470 MHz to 710 MHz, covering the PSME band for global use in the lower UHF range.

Flexible Frequency Operation and Global Applicability

Tuneable RF filtered LPDA antennas, such as the LPDA-A-DT V2, stand out from fixed bandwidth filtered LPDA antennas by providing greater operational flexibility. While fixed bandwidth designs are limited to a single frequency band, tunable models allow users to adjust their operational range and utilise multiple frequency bands as needed. The LPDA-A-DT V2 exemplifies this tunable approach, featuring a filter design that permits operation across a range of 470 MHz to 710 MHz. This wide tuning capability ensures coverage of the PSME band, making the antenna suitable for global deployment within the lower UHF spectrum.

Dynamic Frequency Adjustment and Signal Integrity

A major benefit of tunable RF filters is their ability to adjust their frequency range dynamically. By selectively reducing unwanted signals, these filters improve signal integrity and minimise interference from adjacent channel signals.

Operational Modes

The LPDA-A-DT V2 accommodates diverse needs by functioning in both active and passive modes:

• Narrow-Band Digitally Tuned (DT) mode: Tunable in the 470-702MHz range with a nominal 24MHz bandwidth, adjustable in 8MHz increments. A user-adjustable gain of 20dB is available. An optional 48MHz bandwidth, tuneable in 12MHz steps, extends the operating frequency range to 470-710MHz.
• Fixed Bandwidth – WB Mode: Operates within the 470-710MHz range and provides user-adjustable gain of 14dB.
• When DC power is absent, the LPDA-A-DT V2 functions as a High Gain Passive Antenna for receive or transmit operations, with integrated filtering in the 470-710MHz range and passive gain of 5dB.

Digitally Tuned Mode (DT)

In the Digitally Tuned Mode (DT), the band-pass filter is RF tuned to a narrow 24MHz* window, rejecting all frequencies outside this range. This provides robust protection for the receiving system. The digitally tuned band-pass filter is user adjustable in 8MHz* steps via the OLED menu, covering 470 to 702MHz*.

Wide Band Mode (WB)

In Wide Band Mode (WB), an exceptionally low-loss band-pass filter with a fixed bandwidth between 470-702MHz* is employed.

Booster Section and Signal Management

The booster section features a digitally adjustable RF attenuator at the input to guard against RF overload, while the booster gain adjustment post-amplifier compensates for losses due to long antenna extension cables. Both controls are independently user-adjustable. The booster employs a high dynamic range, low noise RF amplifier, ensuring linear gain throughout the tuning range.

Application and Compatibility

The unique design of the LPDA-A-DT V2 provides flexibility and enhanced front-end protection against interfering dirty RF. In DT-Mode, the booster delivers 20dB of user-adjustable gain to compensate for long cable losses, thus enabling increased distance between transmitter and receiver. The LPDA-A-DT V2 is suitable for applications such as filmmaking, documentaries, fixed installations in studios and theatres. It is compatible with any UHF wireless receiving system, whether digital or analogue, and offers a directional coverage pattern.

Construction and Mounting

The LPDA is constructed using advanced multi-layer PCB design techniques with copper-clad epoxy fibreglass, ensuring durability for heavy-duty use in harsh environments. This construction provides both longevity and consistent performance under challenging conditions. The booster box is CNC machined custom-design, aluminium-black anodised, and features water-resistant O-ring mounting. Mounting is straightforward with an integrated thread for direct attachment to a tripod or, using the supplied adaptor, to a microphone stand. Power is via the coaxial cable, a DC source from 10-18V DC.

Product Specifications

Digitally Tuned Mode
Frequency Range (Variant Depended)*		470-702MHz/470-710MHz*
Tuning Step (Variant Depended)*		8MHz/12MHz*
Bandwidth (Variant Depended)*		24MHz/48MHz*
Selectivity		-38dB to -30dB@50MHz min. (across the whole tuning range)
Gain		20 +/- 2dB (user adjustable in 1.0dB steps)
Wide-Band Mode
Frequency Range		470 – 702/470 – 710MHz*
Gain		14 +/- 2dB (user-adjustable in 1dB steps)
OIP3		>+41dBm
Passive Mode (No DC Present)
Frequency Range		470 to 702MHz/470-710MHz* with in-built Band Pass Filter
Passive Gain		+5dB with in-built band Pass Filter – 470-702MHz/470-710MHz*
Connections
RF output		50 Ω Standard BNC-F
Mounting Options		3/8”-16 standard tripod mount 5/8”-27 adapter supplied
Powering
External Power		10-18Vdc, through coaxial cable (reverse power and short circuit protected)
Current consumption12Vdc		125mA +/- 10mA
Outer Case
Dimensions		270x290x90mm
Weight		490g