1. A frequency synthesizer to lock the voltage controlled oscillator (VCO) with a reference frequency, comprising:
a reference frequency;
a phase detector;
a low pass filter to filter out any ac component from said phase detector and to derive a dc control voltage; and
a voltage controlled oscillator, whose frequency is divided by a divider to compare with said reference frequency and is controlled by said dc control voltage, which is applied in two sequential modes: a calibration mode and an analog mode,
wherein said calibration mode locks coarsely said VCO into limited number of discrete frequency steps within a predetermined frequency tolerance of the reference frequency by resetting and holding a coarse calibrated dc control voltage in a coarse digital phase-locked loop, with a calibration clock frequency divided from said frequency of said VCO, and
wherein said analog mode starts with said coarse calibrated dc control voltage, reset and held during the calibration mode, for fine adjustment of said VCO frequency to lock with said reference frequency in a fine phase-locked loop.
2. The frequency synthesizer as described in claim 1, wherein the calibration clock frequency of the digital phase-locked loop is divided from the VCO frequency by a number no higher than the number of said discrete frequency steps.
3. The frequency synthesizer as described in claim 2, wherein the clock frequency of the digital phase-locked loop during the calibration mode divides the VCO frequency by a one half of the number of said discrete frequency steps.
4. The frequency synthesizer as described in claim 1, wherein:
said phase detector for the analog mode comprises a phase comparator and a charge pump, and
said phase detector for said calibration mode comprises a stepper to reset said coarse calibrated dc control voltage into a predetermined number of steps and is disabled to switched to said analog mode when the dc control voltage locks the VCO frequency within a preset tolerance of said reference frequency.
5. The frequency synthesizer as described in claim 4, wherein said stepper comprises a clock, a counter, and a decision-making block to incrementally step-change said coarse calibrated dc control voltage.
6. The frequency synthesizer as described in claim 5, wherein the number of steps is a binary-weighted number.
7. The frequency synthesizer as described in claim 6, wherein said decision-making block is a control unit that selects between enabling and disabling the counter, calculates the value of the VCO dc control voltage, and selects between breaking and reconnecting the PLL for the calibration mode.
8. The frequency synthesizer as described in claim 6, wherein said counter and said decision-making block are finite state machines.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A search information providing apparatus comprising:
a receiving unit, implemented on a processor operatively coupled to a memory, which receives a search request including a search keyword from a user terminal;
a searching unit, implemented on the processor operatively coupled to the memory, which acquires information corresponding to the search keyword as a search result based on the search keyword included in the search request;
an advertisement information memory that stores advertisement information corresponding to a specific search keyword;
an acquiring unit, implemented on the processor operatively coupled to the memory, which acquires the advertisement information corresponding to the specific search keyword from the advertisement information memory when the search keyword included in the search request is the specific search keyword;
a generating unit, implemented on the processor operatively coupled to the memory, which generates a search result page for displaying the search result and a background image based on the advertisement information acquired by the acquiring unit; and
a transmitting unit, implemented on the processor operatively coupled to the memory, which transmits the search result page generated by the generating unit to the user terminal performing the search request including the specific search keyword, wherein
the receiving unit receives, from the user terminal, a registration request for registration of the background image that is displayed in the search result page and in response to receiving the registration request, information associated with the background image is stored,
and
the receiving unit further receives, from the user terminal, a cancellation request for cancellation of the background image registered by the user, and deletes the information associated with the background image that was stored to cancel the registration of the background image.
2. The search information providing apparatus according to claim 1, further comprising:
a user information memory, implemented on the processor operatively coupled to the memory, that stores information regarding a user of the user terminal,
wherein the acquiring unit selects advertisement information corresponding to the information stored in the user information memory among the advertisement information corresponding to the specific search keyword when the search keyword included in the search request is the specific search keyword.
3. The search information providing apparatus according to claim 1,
wherein the receiving unit determines a classification of the user terminal performing the search request,
wherein the advertisement information memory stores advertisement information corresponding to the classification of the user terminal as the advertisement information corresponding to the specific search keyword, and
wherein the acquiring unit selects the advertisement information corresponding to the classification of the user terminal performing the search request as the advertisement information corresponding to the specific search keyword when the search keyword included in the search request is the specific search keyword.
4. The search information providing apparatus according to claim 1,
wherein the acquiring unit acquires advertisement information corresponding to the background image of the registration request instead of the advertisement information corresponding to the specific search keyword included in the search request when the user terminal performing the registration request performs the search request including the specific search keyword.
5. The search information providing apparatus according to claim 1,
wherein the advertisement information memory stores an address of a predetermined page in correspondence with the advertisement information, and
wherein the generating unit adds, to the search result page, a button for accessing the predetermined page corresponding to the advertisement information acquired by the acquiring unit based on the address of the predetermined page stored in the advertisement information memory.
6. The search information providing apparatus according to claim 5, wherein the button has a color andor a shape according to an image based on the corresponding advertisement information.
7. The search information providing apparatus according to claim 1, further comprising:
a content memory, implemented on the processor operatively coupled to the memory, that stores a content to be provided to each user terminal;
a deciding unit, implemented on the processor operatively coupled to the memory, that decides a compensation for the provision of the content for each user terminal; and
a determining unit, implemented on the processor operatively coupled to the memory, that determines a use status of the advertisement information corresponding to the specific search keyword for each user terminal,
wherein the generating unit transmits a content page including the content stored in the content memory to the user terminal, and
wherein the deciding unit decides the compensation for the provision of the content based on the determination result of the determining unit.
8. The search information providing apparatus according to claim 1, wherein when information corresponding to the search keyword searched by the searching unit exceeds a predetermined number, the generating unit generates a plurality of search result pages of which each displays the background image and the search results less than or equal to a predetermined number, the background images being different.
9. The search information providing apparatus according to claim 8, wherein the generating unit sets images of which at least one of a color and a size is different as the different background images.
10. A search information providing method comprising:
(A) receiving, by a computer, a search request including a search keyword from a user terminal;
(B) acquiring, by the computer, information corresponding to the search keyword as a search result based on the search keyword included in the search request;
(C) acquiring, by the computer, advertisement information corresponding to a specific search keyword from an advertisement information memory that stores the advertisement information corresponding to the specific search keyword when the search keyword included in the search request is the specific search keyword;
(D) generating, by the computer, a search result page for displaying the search result and a background image based on the advertisement information acquired in the (C) acquiring; and
(E) transmitting, by the computer, the search result page generated in the (D) generating to the user terminal performing the search request including the specific search keyword, wherein
the receiving includes receiving, from the user terminal, a registration request for registration of the background image that is displayed in the search result page and in response to receiving the registration request, information associated with the background image is stored,
and
the receiving includes receiving, from the user terminal, a cancellation request for cancellation of the background image registered by the user, and deletes the information associated with the background image that was stored to cancel the registration of the background image.
11. A search information providing apparatus comprising:
a receiving unit, implemented on a processor operatively coupled to a memory, which receives a search request including a search keyword from a user terminal;
a searching unit, implemented on the processor operatively coupled to the memory, which acquires information corresponding to the search keyword as a search result based on the search keyword included in the search request;
an advertisement information memory that stores advertisement information corresponding to a specific search keyword;
an acquiring unit, implemented on the processor operatively coupled to the memory, which acquires the advertisement information corresponding to the specific search keyword from the advertisement information memory when the search keyword included in the search request is the specific search keyword;
a generating unit, implemented on the processor operatively coupled to the memory, which generates a search result page for displaying the search result and a background image based on the advertisement information acquired by the acquiring unit; and
a transmitting unit, implemented on the processor operatively coupled to the memory, which transmits the search result page generated by the generating unit to the user terminal performing the search request including the specific search keyword, wherein
the receiving unit receives, from the user terminal, a share registration request for registration of the background image of the search result page that is displayed on a terminal of another user and in response to receiving the share registration request, information associated with the background image is stored, and
wherein the receiving unit further receives, from the user terminal, a cancellation request for cancellation of the background image registered by the user, and deletes the information associated with the background image that was stored to cancel the registration of the background image.