IT9170: ISDB-T Front-End Receiver
IT9170 is a series of highly integrated ISDB-T Full-Segment single-chip receiver consisting of high quality RF tuner front-end and COFDM demodulator to aim for superior performance, ultra-low power consumption, and simple system design of various ISDB-T applications.
IT9170 offers very low total bill of materials (BOM) solutions. It does not require external SAW filters or baluns. IT9170 requires only one power regulator and one crystal to further simplify the system design and reduce the system cost. The ultra-low power consumption feature of the IT9170 makes it the perfect choice for all kinds of ISDB-T applications. IT9170 series also supports many output interfaces, including embedded USB 2.0 interface, and serial/parallel TS interface input/output with built-in de-multiplexer.
IT9170 series is compliant with ARIB STD-B31 ISDB-T Standard, ABNT NBR 15601 Digital Terrestrial Television – Transmission System, and ABNT NBR 15604 Digital Terrestrial Television – Receivers. All modes (Mode 1, 2, and 3), modulations (DQPSK, QPSK, 16QAM, 64QAM), code rates (1/2, 2/3, 3/4, 5/6, 7/8), guard intervals (1/4, 1/8, 1/16, 1/32), time-interleaving depths, and partial reception are supported and automatically detected from the TMCC parameters.
Depending on the reception status, IT9170 continuously adjusts the states of its internal modules to avoid unnecessary power consumption and hence it can achieve the maximal power saving. The integrated RF tuner of IT9170 provides front-end frequency down-conversion for applications over 90 - 862 MHz.
The Zero-IF direct conversion architecture of IT9170 achieves low power consumption and the integrated dual analog-to-digital converters (ADC) are capable of delivering the performance required for all modulations and code rates of ISDB-T. The single-ended RF input architecture of IT9170 eliminates the requirement of baluns. The integrated RF loop-through of IT9170 also eliminates the need for external active circuits for splitting RF power.
IT9170 AGC control loop bandwidth is designed to track a wide dynamic range of the received signal levels for slow or fast channel variations. The automatic RF/BB AGC gain distribution properly compromises the performance between noise and linearity.
In IT9170, an active impulse noise rejection algorithm removes the detrimental effects of the impulse noise and significantly improves the robustness of TV reception against interference from vehicles and electrical appliances.
IT9170 uses the most advanced digital signal processing techniques to combat various impairments encountered in transmission channels. Co-channel interference is actively searched and rejected by sophisticated digital signal processing in IT9170. Adjacent Channel Interference (ACI) is rejected by precisely controlled digital filters. The Integrated Received Signal Strength Indicator (RSSI) further yields precise AGC adjustment in the environments with ACI.
The all-digital synchronization tracking loops of IT9170 are capable of recovering carrier frequency offsets as large as ± 500 kHz and tolerating crystal jitters as large as ± 100 ppm. The adaptive FFT window position tracking loop in IT9170 accurately identifies pre-echo or post-echo multi-path channels even in highly mobile environments. Therefore, inter-symbol interference (ISI) and inter-carrier interference (ICI) is greatly reduced.
In IT9170, the common phase error caused by tuner phase noise is corrected by a joint channel estimation and phase noise tracking algorithm to improve the robustness to RF imperfections.
IT9170 provides a comprehensive set of performance monitoring parameters accessible. These parameters include signal strength and signal quality indicators, post-Viterbi bit error rate, Reed-Solomon packet error rate, TMCC lock, and TS Sync lock indicators, carrier and crystal offsets, and many more.
A complete set of application programming interface (API) is available, facilitating fast and easy integration into products. Furthermore, a complete set of USB drivers on Windows 7/XP/Vista with Microsoft BDA (Broadcast Driver Architecture) compliant and on Windows Mobile/CE are provided for IT9170.
