Terrestrial broadcast is a technology that is undergoing a dramatic change. The scarcity of spectrum, the desire to pack high definition or even 3-D video into existing spectrum and the ever present desire to reduce CAPEX and OPEX costs are all catalysts driving the transition from analog to digital broadcast. With power amplifier output power levels ranging from 1 W to in excess of 1 kW, manufacturers of broadcast equipment are motivated to find solutions that will not only support the new digital standards but also help reduce solution and operational costs. For 1 W transmitter, using predistortion to linearize the amplifier could be considered a “nice to have”; at 600W it is an absolute necessity.
Unfortunately, predistortion solutions have been out of reach for many equipment manufacturers due to complexity and costs. With Scintera’s SC1887-03 RFPAL and its unique RFin / RFout architecture, predistortion technology is now available to any broadcast equipment vendor. The SC1887-03 is elegantly simple to use and easily integrated into existing UHF transmitter designs. Many customers have been able to achieve impressive linearization and efficiency improvements within ½ a day of receiving their evaluation kit.
Using the 600 W example above, the SC1887-03 could save the television operator in excess of $2000 a year in electricity alone compared to operating the amplifier in backoff. See the benefits for yourself using Scintera’s System Efficiency & Power Consumption Calculator.
Note: Due to the reason described above, PA device vendors have optimized their devices to be natively linear – meaning that these devices are expected to meet linearity requirements without predistortion. With these types of devices, the SC1887-03 can typically achieve 8 dB of correction. With devices optimized for peak power instead of linearity, the SC1887-03 can provide 20+ dB of correction, cut the device size in half, lower the system power consumption by 70% or more and still meet or exceed the original system linearity requirements.
Applications:
- Modulation: DVB-T, CMMB, DTMB, ISDB-T & ATSC
- Instantaneous signal bandwidth: up to 10 MHz (for support of 6 MHz and 8 MHz channels)
- Frequency of operation: 470 MHz to 862 MHz
- Digital terrestrial UHF amplifiers, drivers, exciters and transmitters
Wide range of PAs and output power levels:
- Amplifier: Class A/AB, Doherty
- Average PA output power: 1 W to 600W – Note: Higher power possible depending on system linearity requirements
- Process: LDMOS and GaN
