Table of Contents
Advertisement
U8185
Maintenance Manual
The reception channel includes the antenna, duplexer, RTR6285A's internal LNA and receiver,
and external single-ended to differential filter. Reception channel: Signals are received from
the antenna > After frequency selection and filtering on the duplexer, receiving signals are
transmitted to the RF receiver > Signals are amplified by the LNA > Signals are processed by
the single-ended to differential filter > Signals are amplified > Signals are modulated by
Quadrature Downconverter and become I/Q signals > After analog-to-digital conversion
(ADC), signals are transmitted to CPU for processing.
Troubleshooting Process
Failure: No transmission; the phone cannot initiate or receive a call, or access the network.
Solution:
Issue 1.0 (2012-03-23)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
9 Principles and Failure Analysis
41
Advertisement
Table of Contents
