tune up procedure

FCC ID: J9COVMCPSDM1

Parts List/Tune Up Info

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FCCID_652334

SDM FCC Certification Report Operational Description Chanasgn is the channel assignment given to the terminal for the packet transmission NumChan is the number of return link frequency channels C.4 Tune-up procedure Refer to session C.1 through C.3. C.5 Frequency stability device A voltage controlled, temperature compensated, crystal oscillator (VCTCXO) is employed as a frequency reference for all of the transceiver local oscillators. This crystal oscillator is specified to remain within +/- 8 ppm over temperature and voltage variations. The lock status indicator of all synthesizers is monitored by the microprocessor and an out of lock condition will inhibit transmission. C.6 Spurious suppression C.6.1 Suppression device Reference Part Name Function Designator Provides protection against receive spurious Rx amp filters Image reject BPF emissions and receiver local oscillator leakage Provides protection against transmitter spurious Tx amp filters TX BPF emissions and transmit local oscillator leakage Rx amp mixer Provides protection against receiver local oscillator Rx PA filter filters leakage Tx amp mixer Provides suppression of spurious energy and TX PA filter filters transmitter harmonics Rx IF filter RX_IF BPF Provides other than RX_IF emission Tx IF filter TX_IF BPF Provides other than TX_IF emission SHSH1, 2, 5, 6, 8, 10, Provides on-board shielding of critical circuits that Sheet shields 11, 13, 14, 15, 21 might generate spurious emission Provides suppression of emission from power LC filters numerous switch and digital circuit C.6.2 Frequency hopping correction factor The RF spurious emissions being radiated in carrier-on state by the SDM are harmonically related to the local oscillators (and their mixed products) in the digital 80-JXXXX-X Rev. A QUALCOMM Proprietary C-9

Operational Description SDM FCC Certification Report and RF CCA. The local oscillators are tuned to different frequencies every 20 ms (half of the hopping period) to switch between the receive frequency and the hopped transmit frequency and vice versa. Due to this constant re-tuning of the local oscillators, the frequencies of the spurious emissions are constantly changing, or hopping, every 20 ms as well. This hopping of the spurious emissions allows us to spread their power over the entire hopping bandwidth (36 MHz for domestic system) of the transmitted signal. If the measurement bandwidth is 100 kHz, there is a spreading factor of: ⎛ 36,000 ⎞ 10 log⎜ ⎟ = 25.6 dB ⎝ 100 ⎠ The hopping of the spurious emissions can also be seen in factory mode by setting up the spectrum analyzer to measure a spurious emission in any given 100 kHz band, and simply changing the transmit frequency on the display unit screen. The spurious response of the SDM will change depending on the transmit frequency in hopping. The above spread factor of 25.6 dB can be taken into account in the measurement of carrier-on spurious emissions. C-10 QUALCOMM Proprietary 80-JXXXX-X Rev. A


Document Created: 2006-04-28 09:40:03
Document Modified: 2006-04-28 09:40:03
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