Cisco Systems UBR7225VXR specifications Electrical Input and Output

Appendix B RF Specifications

Electrical Input and Output

Electrical Input and Output

The information in Table B-9and Table B-10relates to both DOCSIS and EuroDOCSIS specifications.

		Table B-9	Electrical Input to the Cable Modem
		Parameter		Value
		Center frequency		• DOCSIS: 91 to 857 MHz ±30 kHz
				• EuroDOCSIS: 112 to 858 MHz ±30 kHz
		Level range (one channel)		• DOCSIS: –15 dBmV to +15 dBmV
				• EuroDOCSIS: 43 to 73 dBmicroV for QAM-64
					47 to 77 dBmicroV for QAM-256
		Modulation type		QAM-64 and QAM-256
		Symbol rate (nominal)		• DOCSIS: 5.056941 Msym/sec (QAM-64) and 5.360537
					Msym/sec (QAM-256)
				• EuroDOCSIS: 6.952 Msym/sec for QAM-64 and
					QAM-256
		Bandwidth		•	DOCSIS: 6 MHz
					– 18% square root raised cosine shaping for QAM-64
					– 12% square root raised cosine shaping for QAM-256
				•	EuroDOCSIS: 8 MHz
					– 15% square root raised cosine shaping for both
					QAM-64 and QAM-256
		Total input power (40–900 MHz)		< 30 dBmV (90 dBmicroV)
		Input (load) impedance		75 ohms
		Input return loss		• DOCSIS: > 6 dB (88–860 MHz)
				• EuroDOCSIS: > 6 dB (85–862 MHz)
		Connector		F connector per ISO-169-24 (common with the output)
		Table B-10	Upstream Electrical Output from the Cable Modem
		Parameter		Value
		Frequency		• DOCSIS: 5 to 42 MHz edge to edge
				• EuroDOCSIS: 5 to 65 MHz edge to edge
		Level range (one channel)		• QAM-16: +8 to +55 dBmV (+68 to +115 dBmicroV)
				• QPSK: +8 to +58 dBmV (+68 to +118 dBmicroV)
		Modulation type		QPSK and QAM-16
		Symbol rate (nominal)		160 ksym/sec
				320 ksym/sec
				640 ksym/sec
				1280 ksym/sec
				2560 ksym/sec
	Cisco uBR7225VXR Universal Broadband Router Hardware Installation Guide
B-8					OL-17309-02