S-Band Bandpass Filter
S-Band Bandpass Filters: The Main Characteristics
In these times, new technologies are making it easier for mobile phone companies, satellite operators, defense contractors, digital audio creators and distributors, as well as medical equipment makers, because of items that are called “band pass filters”. These devices “attenuate” or reduce/lessen frequencies that are outside an applicable or given band range. And with different frequencies on the radio spectrum, let’s first take a brief look at the capabilities of S-band filters.
What The S-Band Means
S-band pass filters work best in their specified band range, which of course is the S-band. The S-band is actually part of the microwave band of the electromagnetic realm or spectrum, and it’s defined by the IEEE or Institute of Electrical or Electronics Engineers. Standard for radio waves with frequencies which range from 2 to 4 GHz, and crosses the standard boundary between UHF and SHF at 3.0 GHz.
Who mainly uses the S-band?
Electronics experts say that the S-band is used for surface and ship radar, weather radar, many communication satellites (like the ones used by NASA for communicating with the International Space Station or Space Shuttle). The S-band ranges roughly from 2 to 4 Ghz.
ABPF-3300MBW400-01 – 3.3GHz Cavity Band Pass Filter
ABF-3300MBW400-01 is an S-Band Bandpass Filter by AWG Tech. It has a center frequency of 3.3GHz and an operating bandwidth of 400MHz. The passband frequency is 3.1-3.5 GHz. ABF-330MBW400-01 is a low loss cavity filter and the passband insertion loss is 1 dB max. It is able to reject signals with frequencies less than 2.9GHz and from 3.7GHz to 11 GHz by more than 50dBc.
| Parameter | Specification |
|---|---|
| Center Frequency | 3.3 GHz |
| Passband Frequency | 3.1GHz – 3.5 GHz |
| Bandwidth | 400 MHz |
| Insertion Loss | 1.0 dB max |
| VSWR | 1.5:1 max |
| Rejection | > 60 dBc @ dc – 2.9 GHz > 60dBc @ 3.7 – 11 GHz |
| Connectors | SMA (F) |
The Main Applications Of S-Band Bandpass Filter
S-band filters, like the other filters utilized for filtering the other frequencies in the radio spectrum, come in various shapes and configurations, and are designed or manufactured to perform certain functions too.
Most of today’s S-band filters are used in various defense radar applications for long-range naval, army and air force surveillance and tracking (and development of missile sensors), commercial airport radars, and for scientific applications like weather tracking and ground surveillance.
In one type of S-band filter, the configuration is composed of two sections, which consist of three coupled lines, and are separated by a non-uniform line resonator. And in order to introduce transmission zero at each edge of the desired pass band, one of the filter’s outer couple lines of each section is shorted to the ground.
This S-band filter’s non-uniform resonator is also constructed by attaching a pair of capacitive open-ended stubs at its central location. This filter is generally designed to have a very wide passband, to effectively cover the whole S-band frequency realm.
Today, the S-band catalogue includes a wide number of satellites (both commercial as well as government-owned) in synchronized orbits, as well as those in inclined, eccentric orbits or HEO’s. Low-orbiting satellites also utilize the S-band.
Back on earth, the S-band is also widely used by wireless network systems and components which are in tandem with IEEE 802.11b and 802.11g standards, all of which utilize the 2.4 GHz section of the S-band. A number of digital cordless phones operate on the S-band, as well as microwave ovens which operate at 2495 or 2450 MHz.
S-band pass filters also work wonders for amateur radio and amateur satellite operators, especially those who operate the 13 cm (2.4 GHz) and 9 cm (3.4 GHz). These filters work great with amateur television repeaters too.