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宽带接收机使用固定的本振将频率典型地为900MHz信号向下变换到基带从5MHz到25MHz的信号——并且直接变换成数字量。许多独立的信号通道包括了滤波,解调和数字的处理。那些用于基站的系统减少了价格和复杂程度——它们仅需一个单独的高频模拟前端,但是关键的连接即A/D变换器必须具有优良的特性。用于宽带接收机的A/D的特性受到系统无线电标准的驱动。为了在很强的领近信号的存在中接收远距信号,蜂窝基站接收机必须具有很宽的动态范围。例如GSM特性要求接收机在许多其它信号存在的情况下(详见图 1)应能精确地对-13dBm至-104dBm的信号进行数字化——这意味着应具有91dB的动态范围!这同样意味着变换器和模拟前端的无伪动态范围(SFDR)必须达到95至100dBFs。
Broadband receivers use fixed local oscillators to down convert a signal of typically 900 MHz to a baseband signal from 5 MHz to 25 MHz - and convert directly to a digital quantity. Many independent signal channels include filtering, demodulation and digital processing. Systems for base stations reduce the price and complexity - they require only a single high-frequency analog front end, but the key connections, A / D converters, must have excellent features. A / D features for wideband receivers are driven by system radio standards. In order to receive long-range signals in the presence of a strong near-end signal, the cellular base station receiver must have a wide dynamic range. For example, the GSM feature requires that the receiver should be able to digitize signals from -13 dBm to -104 dBm accurately, with many other signals present (see Figure 1 for more detail) - which means that there should be a 91 dB dynamic range! This also means The pseudo-dynamic range (SFDR) of the converter and analog front end must reach 95 to 100dBFs.