Limited Fan-out Handover Test Systems for Cellular Testing

Whether you are fading multiple base station signals to a handset or testing multiple communication standards with wireless devices, JFW has a handover test system to help automate your RF testing. JFW's limited fan-out configuration (LC) handover test systems are scaled down versions of our full fan-out handover test systems. These limited fan-out models have individually controlled programmable attenuators on the input ports. All of the input signals are summed together and then split up to all of the output ports. This type of construction allows an input signal to be available to all output ports at the same attenuation level. Because the limited configuration models use fewer RF components than the full fan-out models, the cost of the limited configuration models is lower. Example block diagrams are located below the model selection table. For your specific application, please contact JFW for assistance or use our Inquiry Form. [lt id="80"]

LC Handover Test System Example

The below block diagrams show examples of a 4 X 2 limited fan-out configuration (LC) handover test system. Each input port has its own individually controlled programmable attenuator. The input signals are summed together by the 1X4 divider/combiner and then split to both output ports by the 1X2 divider/combiner. An input signal is simultaneously available to both output port at the same attenuated level. The isolation between the two output ports is determined by the isolation of the 1X2 divider/combiner. Reactive power divider/combiners typically have 20dB of port to port isolation. The isolation between input ports is determined by the isolation of the 1X4 divider/combiner. Keep programmable attenuators on unused paths at their maximum attenuation setting in order to maximize input to input isolation.

Block Diagram #1

This block diagram illustrates the construction of the 4 X 2 limited fan-out configuration (LC) handover test system. It shows all of the connectivity between the input ports and the output ports. This design allows the RF signal on input #1 to be simultaneously available to both outputs at the same attenuation level.

Block Diagram #2

This block diagram shows one possible setting of the 4 X 2 limited fan-out configuration (LC) handover test system. There are four input signals (red, blue, green, purple). The 1X4 divider/combiner sums up all of the input signals. The 1X2 divider/combiner splits the signals up to both output ports. Attenuators #1 and #2 attenuate their input signals at 0dB. Attenuators #3 and #4 attenuate their input signals at 0dB. The output signal for output #1 is identical to the output signal on output #2.

Block Diagram #3

This block diagram shows another possible setting of the 4 X 2 limited fan-out configuration (LC) handover test system. There are four input signals (red, blue, green, purple). The 1X4 divider/combiner sums up all of the input signals. The 1X2 divider/combiner splits the signals up to both output ports. Each programmable attenuator is set to a different attenuation level (0db, 3dB, 6dB, 9dB). The output signal for output #1 is identical to the output signal on output #2.

Custom Models

JFW does not charge NRE's for custom test system models. Please email us your specific requirement. We will respond with a ROM (rough order of magnitude) quote in 1-2 days.

Remote Commands

The handover test system models are available with Ethernet/Serial remote control.  Our current generation of Ethernet/Serial firmware is called 3.x.x firmware. It features easy to use ASCII formatted remote commands. Use our Ethernet Test Box to demo the 3.x.x firmware.

Test Software

JFW provides a GUI test program with all Ethernet and RS-232 controlled test systems. The test software for handover test systems has all of the remote commands built in for easy testing. Jump to our sample test programs to see example programs.