Instantaneous Frequency Meter Boards for radar pulses

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Important Note:

What is shown in the photo galleries is the unavoidable minimum necessary to demonstrate and offer this experience to this new global market, but this presentation is only a panoramic view with no useful details of the projects done for other companies.
               
Correlator to IFM board covering 2-18 GHz band

Instantaneous Radar Phasor to Frequency Converter Board. This unit operates in parallel with a microwave correlator module that covers the entire radar microwave spectral range in GHz, and converts the two orthogonal signals generated by the correlator at hundredth MSPS into very high resolution digital words, then calculates the relative phase angle between these signals, and sends the data as an address of a large calibration table on a computer memory to extract the frequency, all that for radar pulses down to the nano second pulse widths

This is a multi-layer board completely designed and routed for maximum speed and minimum noise levels to attain high resolution ADC. The unit also has an ADC for the pulse amplitude generated by a fast Detector Logarithmic Video Amplifier. The ADC also takes hundredths of MSPS at very high resolution. One aspect of this design is the need to use linear voltage regulators local for each ADC placed close to the chips, and the need to use regulator chains to increase the noise rejection ratio. Extensive consideration was taken in relation with microwave models for almost all components.
   
 
Correlator to IFM board covering 2-18 GHz band, ORCAD schematic  

The schematics are drawn using several CAD/CAE tools with several objectives in mind: They should be as easy to understand as possible, symmetry, hierarchy, well balanced function blocks, good block spacing, obvious signal and bus naming, expressive graphics for integrated circuit macros to easy suggest their functions, and connectors shown almost physically, a design that includes the least items possible, a schematic with clear and brief notes on settings and calibration procedures, all that to easy fabrication and maintenance. Schematics are later exported to the client in Adobe.
 
High Speed sequencer board, an intermediary to a PCI FIFO board Real Time Data Sequencer Board. This unit receives the already digitized characterization parameters of each received radar pulse, say instantaneous amplitude in dBm along a very large amplitude dynamic range, pulse width in nano seconds [ns] up to continuous mode, instantaneous frequency in MHz from VHF up to centimeter spectral range, angle of arrival, in degrees, and several other intrapulse variables. Then the unit assembles a large vector field in a format to be correctly interpreted by a PCI FIFO board in a computer. All this is done in real time.
 
Schematic of High Speed sequencer board, an intermediary to a PCI FIFO board Radar signal processing boards must execute many calculations instantaneously, so all these boards use one or more “Field Programmable Gate Arrays” VLSI circuits to synthesize all these math operations. FPGAs are a new kind of integrated circuit invented and produced by Xilinx Inc., of San Jose, CA. (http://www.xilinx.com ) The gate density of these FPGAs is rapidly reaching the multi-millions gate level, and the math operations can be done at nano second speeds, much faster than any Von Newman like CPU, however higher level software processes and graphic user interfaces must still be done by a computer that receives all this pre-processed data
 
An all digital IFM board, used to encode 256 bands between 2-18 GHz.

All-digital Instantaneous Frequency Measurement Board. For the moment it functions as a companion board to the Instantaneous Radar Phasor to Frequency Converter Board, providing the equivalent to a microwave filter bank with several hundreds of band pass filters, thus allowing the generation of phasor curves within hundreds of thin spectral bands. This allows increasing greatly the instantaneous frequency resolution of the system, down to the hundred kilohertz range along the entire radar band spectral range.

This multi-layer board includes a high speed Xilinx FPGA for ultra fast parallel math algorithms, and uses special microwave ICs SMT mounted on coplanar wave guides calculated with Agilent´s AppCAD software. One special aspect of this design is the power dissipated by high speed circuits, in special the NECL prescalers and translators. Extensive use of linear regulators was necessary to avoid noise spikes mounting over these delicate signals, and pseudo random switching regulators were also avoided, because they are just a trick to comply FCC regulations, but they produce the same noise spikes.
 
 

)  Once the board is installed in a system, the infinite reprogramability of the Xilinx FPGA allows inventing almost unlimited new math algorithms. One of the most intriguing thing is to figure out how far can go the creativity of other engineers invited to do "gateware" for these boards. This is a new kind of “software” referred to a “gateware” where many math events can flow in parallel, as in an assembly line where several products are being fabricated at once. These multi-layer boards are assembled with fine instruments and microscopes, and the microwave guide geometry is calculated with Agilent AppCAD, a basic software program that allows designing coplanar waveguides.

 

Typical projects time schedules
These board level products are obviously part of major projects, but considering them as individual designs, they use to take some 6 months up to complete all laboratory and field tests. This time involves all the stages from the conceptual idea, the CAD of electronic hardware, the Xilinx "gateware" and the embedded software that may be included if there is an on-board companion processor, the PCB routing by a contractor using the best CAD software, the fabrication in USA or Chile, upon cost/complexity factors, the assembly done by contractors using stereo microscopes, and the laboratory gateware/hardware/software design iterations that may be necessary.

Yes, I admit that most often it is necessary to debug some hardware design errors in laboratory, and for that reason, in the case of 4-layer boards, the two inner layers are mainly for power and ground planes, leaving almost all nets routed on the two external layers.
Schematic of an all-digital IFM board, used to encode 256 bands between 2-18 GHz.
 
 
emsamble This is a typical prototype assembly of a very small part of a major equipment. Prototypes function as test benches to minimize the risk before the real assembly.  
 
 
Recommended Companies in Chile
   
             

              Contractor Company in Design of Multilayer PCBs, in all projects:

         DIVA     http://www.matharts.cl\diva.cl  Designer of multilayer PCBs, see link right here.

              
              Other Recommended Companies in Chile

              CIGA             http://www.ciga.cl/                  Manufacturer of multilayer printed circuit Boards
              Poirot              http://www.poirot.cl/                Vendor of precision PCB assembly equipment
              Axys               http://www.axys.cl                   Assembles PCBs including all kinds of SMT ICs

              Recommended Companies in the USA
              Manufacturers of high density multilayer PCBs including the most complex BGA ICs, both are located in San Jose CA. Silicon Valley:

              Accutrace                       http://www.accutrace.com/
              Sierra Proto Express       http://www.protoexpress.com/

              Special Soldering Services like soldering ICs packaged in large BGAs and QFN formats
              STI Electronics, Inc.       http://www.solderingtech.com/