Are you searching for a portable and convenient antenna which is an important addition to a radio communications kit? All you need is a rubber duck antenna. These antennas are seen as the most appropriate option if you desire having one that works in a seamless manner and over short distances.
In this article, we will be talking extensively on rubber duck antenna, its efficiency, electrical design, and more. Stay with us to discover if this device is a great fit for your projects.
Basics of an Antenna
An antenna can be described as a device, which helps in converting electromagnetic waves into small electrical signals that can be sent into your radio or TV and vice-versa. Most antennas utilized in radio and television transmission today can be described as the dipole antenna.
They function effectively over any short distance. However, for the longer distances, you will need something else. This is referred to as the antenna array (this is called the phased array antennas). They are composed of different dipole antennas that are grouped together in order to form a larger one. It can pick up different signals sending them to the receiver at once.
The Origin of the Name – Rubber Duck Antenna
There are different rumors linking this antenna name to the John Kennedy family. One of these rumors says that the young daughter of John F. Kennedy (the then U.S. President), Caroline Kennedy named this device when she discovered one on the transceiver of an agent and termed it rubber ducky.
Moreover, a top NASA scientist, Thomas Clark, claims that he created the name of this device from the Vaughn Meader Comedy relating to the Kennedy family. For this type of antenna, there is a term that is less flattering that includes stubby – stubby antennas.
What Does a Rubber Duck Antenna Mean?
Rubber duck antennas can be described as short devices that function as monopole antennas. Furthermore, these devices feature an element with one quarter wavelength. Due to this reason, the linear antenna can be utilized in any portable equipment.
In addition, it features a great capacitive reactance. Hence, it is useful in offering an impedance match that is imprecise. However, first, you need to have the antenna connected in series using an inductor. Summarizing, this rubber ducky antenna is a device having an initial spring antenna that has been confined in rubber-like coverings.
Rubber Duck Antenna Types
There are different shapes, sizes, materials for the rubber duck antennas. Therefore, before choosing one that works best for you, it is important you consider the types. These include:
- Flexible antennas
- Fixed-position antennas
- Wire-clamp antennas
Wire clamps will be the best for you if you need linear element antennas having high efficiency whenever you mount them in open regions or areas. However, if you prefer an antenna that allows you to move around or pack inside tight spaces, then you should choose the flexible antennas. Also, fixed position antennas would be the best choice if you must place linear antennas at a specific height or location.
Efficiency of the Rubber Duck Antenna
The wavelength of rubber ducky antennas is much larger compared to the length. Also, the rubber duck antenna’s effective aperture can be compared regardless of its small size. Furthermore, monopole antennas usually finish its electrical circuits with a ground plane or opposing force. Older versions will include portable transceivers because ground places are usually a small internal battery or internal shield jacket.
However, if you choose the rubber ducky antennas of today, you will discover that the transceiver cases function as non-conductive plastics. Therefore, this means the antenna would have less efficiency. This is because this device does not have a conductive path, which provides a ground plane or counterpoise.
Therefore, the antennas would function better. In order to boost your antenna’s functionality, make sure that it functions at operating frequencies that are near electrical resonance.
Electrical Design of Rubber Duck Antennas
Although rubber duck antennas feature decent performance, their apertures cannot be compared to the larger antennas. In addition, the current distribution of real antennas isn’t sinusoidal. This is why classifying the distribution of the current is difficult. You can work with these rules to design this type of antenna.
- First, when the spring coils possess larger diameters than their array lengths, then make sure the bandwidth of the antenna is narrow.
- Second, the resulting antenna must possess the largest bandwidth possible when there are narrow spring coils in contrast to the length of the array.
- Third, the impedance has to be far less than 50 ohms when the initial spring antenna is pulsating and wide. This means that the impedance has to head to 0 ohms. Larger inductors must be included in the structure. Therefore, the setup would seem like series-tuned circuits having a small radiation resistance value.
- Fourth, the impedance needs to be increased towards 70 ohms when there is a narrow spring and a resonant antenna.
Having these rules, you will easily design linear element antennas with compromised bandwidth at feed points as well as 50 ohm impedance. In addition, few compromises usually apply to the rubber duck antennas on the cell phone tapers.
Cons of Rubber Duck Antennas
- Has less gain due to losses
- Antennas need parabolic reflectors for boosting its performance
- Its current distribution isn’t sinusoidal. Therefore, classifying this antenna electrically is difficult
Differences Between Rubber Duck Antenna and Whip Antenna
Below is a table that shows the differences between rubber duck antennas and the whip antennas, which are usually base-loaded.
Build Design
A rubber coating usually covers the rubber duck antennas. This coating houses the spring wire with helix shape. For whip antenna, it is a straight and flexible iron rod that it linked to radio transmitters or receivers.
Directivity
Rubber duck antennas are usually less direction-sensitive, while the whip antenna with a regular quarter-wavelength has a more sensitive and critical directivity.
Plane positioning
Aiming rubber duck antennas at specific planes is exemplary while pointing the whip antennas to a specific plane is bad.
Angle Range
For the vertical field, rubber duck antennas measure 30:30 degrees up. The horizontal one measures 60:60 degrees down. For quarter-wave antenna, it has the 60:90 doubling to be its appropriate vertical as well as horizontal angles.
What are the Variations of the Rubber Duck Antenna?
The design of some rubber duck antennas is different from the initial design. A type makes use of a spring just for support. This spring is shorted out electrically. Therefore, this antenna is electrically a linear element type. Some others utilize non-conducting materials for support.
They are also made up of collinear array antennas. These antennas are called the rubber ducky antennas although they act quite differently than the initial spring antenna.
Tips when Buying Rubber Duck Antennas
You can find the rubber duck antenna in almost all applications. It simply involves finding one which works for the antenna installation. Just like all other equipment, you can find both generic and branded models; whatever you choose depends on your personal budget.
The generic type of rubber duck antenna costs around $20 to $25; therefore, they are cheap alternatives to the name-branded versions that usually cost around $35. Make sure you match your unique needs with whatever the antenna offers. Whenever you are purchasing the new antenna, ensure its range of frequency is great for your region and application.
The frequency of the rubber duck antenna can be found between 150 MHz and 5 GHz. However, check that the frequency specifications of the device match up with the selected model. Let’s say that you desire the 800 MHz band for 3G and 2G communications on the LTE networks, you won’t be able to select a model that has been designed for the 2.4 GHz or Wi-Fi networks. This is because they don’t operate or function the 1 GHz.
For this case, you can select a combo antenna, which includes both the directional dish and omni-directional patch. Although they aren’t readily available like the straight duck antenna, both models offer more flexibility regarding the way they are used. Just ensure you purchase one, which suits the needs of your device.
Frequently Asked Questions
Are rubber antennas good? Rubber duck antennas deliver decent gain. However, it offers less gain compared to the regular whip antennas.
Can we refer to the rubber duck antennas as a dipole? You cannot because the rubber duck antenna is not a dipole. Rather, they are short monopole antennas.
What is the nominal gain of rubber duck antennas? Rubber duck antennas have a nominal gain value of 2.2dB.
Conclusion
Compared to other antennas in its category, rubber duck antennas are more affordable, especially for the whip antenna. This is why it isn’t surprising that the majority of engineers want to use them. Also, aside from its narrow bandwidth, rubber duck antennas have a high IQ factor. This factor is common among the majority of antennas with short monopoles.
What are your thoughts about this article? Please you can message us if there is any question bothering you. Hope to hear from you soon!
