Digital Video Broadcast

The Kaben KR-DVB-01 is a low power DVB Tuner IP block for integration into an SoC or for manufacturing a stand alone product.

The Kaben KR-DVB-01 cell has an operating frequency of 50 to 860 MHz for reception anywhere in the world.

For Satellite channels, a millimeter wave LNB unit proceeds the tuner. For Terrestrial channels and Hand-held channels, the signals are first directed to an off-chip Switchable, Continuous Time filter which provides some light filtering to help address the near-far channel problem.

The complete band is then amplified in an LNA having a delayed AGC, and passed to the first SIF. This first SIF is tunable over the complete broadcast band extending from 50 MHz to 860 MHz, and has a passband bandwidth of 80 MHz, thereby passing 10 adjacent channels, including the desired channel, at a time. The desired channel need not be centered in the passband; in fact, for Terrestrial and Hand-held channel service, the first SIF should be tuned to include the desired channel, while also rejecting at least the closest, high power, undesired channel. To tune over the band of 50 MHz to 860 MHz, the first SIF is clocked with a synthesizer having a VCO running at 10 GHz. The 10 selected channels emerge from the first SIF in a sampled-analog IF form, are amplified (buffered) in a gain stage, and directed to the second SIF. The second SIF isolates the desired channel and passes it, at 36 or 44 MHz, and still in sampled-analog form, to the second AGC amplifier. Finally, the sampled-analog desired channel is converted to analog form for connection to the television's back-end analog circuits for channel equalization, demodulation, error correction, encoding etc.

The first SIF band selection, and the synthesizer clock frequency, are determined by the channel select and control logic. The exact group of 10 channels to be passed by the first SIF, and the corresponding clock frequency to be generated by the synthesizer, is dependent on the presence of near channels having excessive power levels (as will occur in Terrestrial and Hand-held services, but not in Cable or Satellite services). The presence and channel frequency of all high power channels is determined by sensing, intermittently, the power level at the output of the first SIF.