S. G. R. Technologies

Antenna is an electronic component designed to transmit or receive radio waves. Prior types of antennas include wired antenna, Omni Antenna, Whip Antenna, Patch panel antenna, Yagi-uda Antenna and printed antenna. The wired antenna is a metallic or conductive wire looped around a core to form a coil. It is normally used for low-frequency electromagnetic waves transmission. Omni Antennas, Whip Antennas have magnetic base and Coaxial cable. It can be used for GSM, EGSM and CDMA data transmission.

The Cell Phone Jammer is an instrument used to prevent cellular phones from receiving and transmitting the mobile signals to a base station. When the Jammer is used it effectively disables mobile signals in the area. These devices can be used in any location, but are found primarily in places where a phone call would be particularly disruptive. These include churches, mosques, libraries, movie theaters, meeting rooms, and other places where silence is expected.

Application Areas

• Church/Mosque/Cathedral/ Temple/ Religious establishment
• Hospitals, Museums, Casinos, Clubs
• For ICU & Operation Theatre
• To keep solemn mode in religious ceremony by removing unwanted noise of mobile phones
• Other public places such as Petrol stations
• Schools, Military Establishments, Court Houses, Government Buildings.
• Theatres (concert halls, playhouses, opera houses, movie theatres, etc.)
• Sporting Events (championship tennis and golf tournaments, etc.)
• Law Enforcement Facilities
• Military Installations
• Private Property and Residences
• Mobile Phone Free Zones and Prohibited Areas
• Prisons (Mobile Jammer High Power)

SGR's directional couplers cover the frequency range of HF through 10 GHz with coupling coefficient varying from 10 dB to 40 dB. Directional Couplers are basically 4 port devices with the fourth port terminated in a matched load either internally or externally. They separate and sample signals based on the direction of signal propagation Directional Couplers may be classified as narrow band and broad band couplers. Narrow band directional couplers are of single section design and are a quarter wavelengths long. Broad band couplers contain multiple quarter wavelength sections. Directional couplers handling power levels up to 1 kW are available in the frequency range of 2 MHz to 1 GHz and are developed using round rod construction. Our directional couplers are widely used in precision microwave systems, instrumentation and measuring systems.

Applications :

Directional couplers find wide applications in RF / Microwave networks, systems and in microwave measurements. They perform variety of signal processing functions such as:

• Power splitting and sampling from signal sources for level control and monitoring.
• Separation of incident and reflected signals in network analyzers for reflection, measurement etc.

SGR filters are available for Low pass, High pass, Band pass, Band reject and Duplexer functions in different configurations with different types like lumped, mechanical cavity or distributed elements. The filters cover the frequency range from DC to 12 GHz, for narrow and wide bandwidth applications. Filter configuration in each type is of LC type, Cavity type or Combl ine type.

LC Filters

LC filters have the most cost-effective designs. These are usually smaller in size, as filter elements are realized using air core inductors or ferrite inductors and mica or chip capacitors.
Comb line Filters

Comb line filters are realized using distributed inductors or lengths of transmission line and distributed capacitance or lumped capacitance. Comb line filters feature high Q, compact size and bandwidths ranging from 2 to 25%.
Cavity Filters.

High Q can be achieved by employing cavity resonators, resulting in low loss and narrow bandwidths. Cavity filters are relatively easy to manufacture. The bandwidth of a cavity filter is determined by the aperture size between the cavities. Larger aperture leads to wider bandwidth of the filter.


SGR Duplexer series of filters allow simultaneous receiver / transmitter operation through a common antenna port. These filters cover frequency bands from 10 MHz to 3000 MHz. and also give good isolation between transmitter and receiver. These filters operate the power up to 1W-100W.

LOW PASS FILTERS

Low pass filter passes the RF signals up to cut-off frequency and attenuate above cut-off frequency. Low pass filters are used to suppress noise and unwanted harmonics from transmitter/Receiver.

The features of the Low Pass Filters are:

• Operating frequency : Up to 12GHz
• Insertion Loss : Low Insertion Loss
• V.S.W.R. : Low
• Design technique : Available in lumped element, strip line and micro strip line
• Size : Compact

BAND PASS FILTERS

SGR's Band Pass Filters are available in the frequency up to 10GHz. These filters have very low insertion loss and high rejection. SGR has expertise in development of Band Pass Filters for GSM and CDMA applications and also applicable for mobile / cellular communication. We can design all types of filters as per customer specifications.

Various band pass Filter configurations used are :
• High 'Q' Cavity Filters
• Interdigital
• Helical
• Lumped

Power Amplifiers can be divided into CW Amplifiers and Pulsed Amplifiers depending upon their application. Further depending upon their output level they are classified as Low Power Amplifiers, Medium Power Amplifiers and High Power Amplifiers. With the advancement of Microwave Integrated Circuit technology and the GaAs FET device technology, highly compact, high performance, low noise power amplifiers for commercial and military applications can be realized to utmost customer satisfaction.
The parameters that characterize the overall performance of an amplifier are gain, noise figure, output power at 1 dB gain compression point, input / output VSWR, saturation output power, third order intercept point, dynamic range etc.