Signal Conditioning DC Offset Removal via Segmented Reset
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In passive optical networks, AC coupling capacitors between transmitters and receivers often face issues due to input-level dependent DC offsets, leading to inadequate signal recovery, especially when host reset signals are insufficient or timed incorrectly, resulting in signal transmission failures during data bursts.
Innovation Solution
The use of both off-chip and on-chip signaling allows for optimized electrical signal negotiation between transmitter and receiver devices, enabling efficient DC offset removal and stable signal transmission by controlling the timing and frequency of instructions issued to the devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a host reset signal is used to discharge AC coupling capacitors, then DC offset removal is achieved, but adequate discharge time is not provided and signal transmission fails
Solution Approach 1:
The receiver generates a preliminary reset signal before the data burst arrives to pre-discharge the AC coupling capacitors. This preliminary action ensures that when the data burst arrives, the capacitors are already discharged and ready to properly process the signal, eliminating the timing conflict between capacitor discharge and data reception.
Solution Approach 2:
The reset signaling is segmented into separate transmitter-directed and receiver-directed signals. The host reset signal is divided such that one portion controls the transmitter and another portion (or internally generated equivalent) controls the receiver's capacitor discharge timing, allowing independent optimization of each device's reset timing without mutual interference.
2Adaptability or versatility
If no host reset signal is provided during registration period, then transmitter output signals remain toggled, but signal transmission fails
Solution Approach 1:
The receiver autonomously generates reset signals for both itself and the transmitter during the registration period without requiring external host intervention. This self-service capability allows the system to properly initialize and discharge capacitors in registration mode, enabling reliable signal transmission in both mission and registration operational modes.
Solution Approach 2:
The system dynamically adjusts its reset signal generation based on the operational mode. During mission mode, the system responds to host reset signals, while during registration mode, it autonomously generates appropriate reset signals. This dynamic adaptation ensures optimal performance across different operational scenarios.
3Measurement precision
If host reset signal timing is optimized for transmitter, then receiver capacitor discharge is insufficient, but signal recovery fails
Solution Approach 1:
The reset control is segmented into separate pathways for transmitter and receiver. The host reset signal is divided such that the transmitter receives one timing sequence optimized for its signal conditioning, while the receiver independently generates or receives a separate reset signal timing optimized for capacitor discharge, allowing both functions to operate at optimal timing without compromise.
Solution Approach 2:
An internal controller within the receiver acts as an intermediary that receives the host reset signal and translates it into appropriately timed control signals for both the transmitter and the receiver's own capacitor discharge circuitry. This intermediary function allows the system to coordinate multiple reset operations with different timing requirements from a single host signal.
Data Source
AI summary
After transmitting first electrical signals to a receiver, a transmitter receives a burst absent mode signal from the receiver. While in a ready state, the transmitter receives a signal including a data burst, converts the signal to second electrical signals, including a settled DC offset, and transmits the second electrical signals to the receiver. The receiver transmits the burst absent mode signal to the transmitter after receiving the first electrical signals, detects a presence of the second electrical signals. In response to detecting the presence of the second electrical signals, the receiver removes the DC offset from the second electrical signals to generate output signals, and causes transmitting the output signals to a subsequent device. The receiver removes the DC offset by causing an instruction to discharge AC coupling capacitors. The burst absent mode signal is generated using a host reset instruction or an internally generated instruction.