Invalidity dossier
US 6549761
Added 9/23/2026, 10:02:19 PM
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Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 6549761 B1
Title: Radio frequency transmission control apparatus for preventing oscillation in wideband wireless local loop terminal
Key bibliographic data (from source): Application US09/518,400; filed 2000-03-03; granted/published 2003-04-15; priority date listed as 1999-03-04; inventor Cheul-Hong Kim; original assignee Hyundai Electronics Industries Co., Ltd.; current assignee listed as Pantech Corp. Status listed as "Expired – Lifetime," with anticipated expiration 2020-03-03. Classifications include H04W88/02, H04B1/0475, and H04W84/14 (WLL).
Purpose: The invention relates to a radio frequency processing apparatus of a wideband wireless local loop (W-WLL) terminal. Specifically, it addresses a radio frequency transmission control apparatus for preventing oscillation, in which power supply is controlled according to characteristics of each active element of a W-WLL terminal's radio frequency transmitting unit, thereby eliminating oscillation caused by simultaneous power supply and minimizing power consumption.
Plain-language scope: A common W-WLL RF transmitting unit (FIG. 3) supplies power to all active elements through a single power line (TX_VCC) when a high-active TXON signal is output from the BBM interface unit. The source states this causes an overload problem and an undesired oscillation frequency as I/Q signals pass via the data buffer to the power amplifier, deteriorating the EB/No of the RF module transmitting output and potentially reducing radio port capacity during wireless communication. It further notes that the power amplifier, which ranks highest in power consumption, may operate while other active elements consume unnecessary power, and that the transmitting unit is turned off after the power amplifier finishes outputting the transmitting RF.
The described apparatus divides the radio frequency transmitting unit into a radio frequency converting unit and a power amplifier unit in accordance with characteristics of each active element. When power is supplied, power is first supplied to the radio frequency converting unit to maintain it in an operating state; after a predetermined time period has elapsed, power is supplied to the power [amplifier unit — text truncated].
What the excerpt does not establish: The full claim language, the complete description of the delayed power-supply sequence, the specific predetermined time period, and the detailed operation of the power amplifier unit. The excerpt is explicitly noted as partial.
Generated 10/1/2026, 9:33:50 PM
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Assignment history
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Prior art
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Obviousness
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