11/6/2007 Rx Specification Sheet 1/3 Jim Stiles The Univ. of Kansas Dept. of EECS Rx Specification Sheet Total Bandwidth (Hz) - Specified as maximum and minimum frequencies in Hz, the total receiver bandwidth is typically defined by the 3dB bandwidth of the preselector filter. If multiple preselectors are implemented, then the bandwidth of each RF band should likewise be specified. LO Bandwidth (Hz) - Specified as maximum and minimum frequencies in Hz, the LO bandwidth is defined as the tuning bandwidth of the receiver Local Oscillator. If multiple oscillators are implemented, then the bandwidth each oscillator should likewise be specified. Intermediate Frequency (Hz) – This is the frequency of the desired signal as it exits the receiver (i.e., enters the demodulator). Typically this is the center frequency of the IF filter. Instantaneous Bandwidth (Hz) - This the bandwidth of the receiver component with the narrowest bandwidth of all the receiver components. Typically, this is the bandwidth of the IF filter, and thus likewise is approximately equal to the bandwidth of the desired RF signal. Additionally, this value is used in determining the noise power at the output of the receiver. Intermediate Frequency Error (+/-Hz) - This value specifies the accuracy of signal frequency as it leaves the receiver. Ideally this frequency is precisely the Intermediate Frequency. However, the Local Oscillator exhibits tuning error (i.e., stability in parts per million). This error translates to an uncertainty in the signal frequency11/6/2007 Rx Specification Sheet 2/3 Jim Stiles The Univ. of Kansas Dept. of EECS as it exits the receiver, an uncertainty specified as +/- Hz (e.g., the Intermediate Frequency error is +/- 10 kHz). Remember, this error should be much less than 10% of the IF bandwidth! Minimum Discernable Signal (dBm) – This value specifies the sensitivity of the receiver. Minimum Output SNR (dB) – The output SNR when the desired RF signal power is equal to MDS. 1dB Compression Point (dBm) – The input signal power where at least one receiver component begins to saturate. Total Dynamic Range (dB) - The difference (in dB) between the 1dB Compression Point and the Minimum Discernable Signal. Image Rejection (dB) - The attenuation (provided by the preselector filter) of an RF signal at the image frequency (of a given tuning solution)—a signal that would otherwise create a spurious response precisely at the receiver Intermediate Frequency 3rd-order Signal Rejection (dB) – The attenuation (provided by the preselector filter) of an RF signal at any and all frequencies that would—for a given tuning solution—create a spurious 3rd-order response precisely at the receiver Intermediate Frequency. Selectivity (dB) – The attenuation (provided by the IF filter) of the RF signals in the channels immediately adjacent to the desired RF signal. Instantaneous Dynamic Range (dB) – The dynamic range of the demodulator.11/6/2007 Rx Specification Sheet 3/3 Jim Stiles The Univ. of Kansas Dept. of EECS Maximum Receiver Gain (dB) – The total receiver gain (input to output) when the smallest AGC attenuation is selected. Minimum Receiver Gain (dB) – The total receiver gain (input to output)when the largest AGC attenuation is selected. Noise Figure (dB) – A value determined when the smallest AGC attenuation is selected. Output Noise Power (dBm) – Assume TA = 290 degrees K. D. C. Power Requirement (Watts) - The total D.C. power requirement, determined by totaling the D.C. power requirements for each component in the receiver
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