Flexible, High-Performance Device Also Targets Digital Radio and Wireless Repeaters
Texas Instruments introduced a new four-channel wideband digital downconverter and upconverter that is ideal for radios in 3G wireless base transceiver systems. The flexible four-channel device is the first chip that provides both digital downconversion and upconversion functions in a single package. Targeted mainly towards CDMA2000 and W-CDMA base station systems, the new device also offers superior digital radio performance for other applications such as wireless repeaters, cable modem radios, wireless instrumentation and defense-based digital radio systems.
TIґs GC5016 enables wireless infrastructure manufacturers to take advantage of the industry's best performance in digital down and upconversion in a single device. It offers outstanding 3G performance with 150 MSPS clocking, flexible wideband digital filtering, many input-output interfacing options and very low power dissipation.
Industryґs Most Versatile Digital Converter
The GC5016 can provide either four channels of digital downconversion, four channels of digital upconversion, or two channels of downconversion and two channels of upconversion simultaneously. Using a single device for downconversion and upconversion for receive and transmit functions, manufacturers can drive costs down for base stations, macrocell, microcell and picocell base stations as well as wireless repeaters. This also means that base station radio engineers need to become familiar with only one device for both downconverter and upconverter functions.
Each of the GC5016ґs four downconverter or upconverter channels can be independently configured. Operating mode, tuning frequency, channel filtering, automatic gain control and input-output options can be programmed over a microprocessor bus. Channel filtering consists of a six-stage CIC filter and a programmable FIR filter. The FIR filter provides up to 255 taps for UMTS and CDMA2000 modes. Spurious-free dynamic range is an industry-best at better than -115 dBC. Power dissipation is about 600 milliWatts when clocking at 100 MHz with four channels configured for UMTS operation. Together, these features provide performance better than any other 3G digital downconverter or upconverter device available today.
Applications requiring wider bandwidth such as cable modem head-end systems, wireless instrumentation and defense/aerospace radio systems can benefit from the GC5016ґs special double-rate input and output mode enabling effective sample rates to 300 MSPS, the fastest in the industry.
In downconversion mode, the GC5016 accepts signal data from an analog-to-digital converter such as TIґs 12-bit 80 MSPS ADS5410. The GC5016 tunes the desired signal to baseband and then isolates the desired signal by applying pulse-shape filtering. The isolated signal is then decimated and output for subsequent chip-rate and symbol rate processing. Further signal processing and demodulation is handled with a programmable DSP chip such as TIґs TMS320C6416 DSP.
In upconversion mode, the GC5016 accepts complex digital signal data from a baseband source. This signal data is then interpolated, pulse-shape filtered, modulated to a programmed intermediate frequency, and then output to an external digital-to-analog converter such as TIґs 14-bit 125 MSPS DAC2904. The GC5016 also supports complex outputs for direct I/Q upconversion and power amplifier digital pre-distortion linearization processing.
Download Free Datasheet Today
Limited preliminary samples of the GC5016 wideband digital downconverter and upconverter are available today from TI at a price of $65 per 1,000 units. Production devices will be widely available in the third quarter of 2003.
