The Commsonic DVB-T2 Modulator core is intended to provide a very efficient FPGA or ASIC implementation of all functions required to take the output from an MPEG-2 transport multiplexer and modulate it according to the DVB-T2 ETSI EN302 755. The DVB-T2 modulator core is compliant with the specification and fully supports 1K, 2K, 4K, 8K, 16K and 32K COFDM modes. The DVB-T2 core features an integrated normal- and short-frame length BCH/LDPC encoder. Whilst L1FIELD padding, encoding and punturing is performed automatically by the core.
The standard output is a baseband I/Q digital pair for direct connection to a DAC. Alternative output configurations include a low IF or direct connection to standard Analog Devices Direct Digital Synthesizers (e.g. AD9857).
Every effort has been made to keep the size of the DVB-T2 modulator to an absolute minimum in order to target the low-cost FPGA families, however this has not been at the expense of functionality. Synthesis directives are used wherever possible to remove a block within the design has functionality that may not be required for all applications.
- 1k, 2k, 4k, 8k, 16k and 32k OFDM.
- BPSK, QPSK, QAM-16, QAM-64 and QAM-256 support.
- Variable 1·7-10MHz bandwidth interpolation.
- Automatic L1 field padding and puncturing.
- Integrated LDPC Channel Coder.
- Short (16kb) and normal (64kb) frames
- All pilot patterns supported, PP1..PP8
- FFT guard interval insertion.
- Optional FFT output windowing.
- External AD9857/AD9957 DDS interface.
- Automatic AD9857/AD9957 programming.
- Optional internal IF conversion.
- Optional in-band pre-distortion.