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EXHIBIT 10.13



                            STOCK PURCHASE AGREEMENT

THIS STOCK PURCHASE AGREEMENT made as of the 18th day of March 2002.

BETWEEN:

               CELERITEK, INC., a corporation duly organized and validly
               existing under the laws of California, having its principal
               office at 3236 Scott Blvd., Santa Clara, California, U.S.A.

               (hereinafter called the "Investor")

AND:

               NEWGEN TELECOM CO., a corporation duly organized and validly
               subsisting under the laws of the Republic of Korea, having its
               principal office at 2nd Floor, Duk-Myung Building A Dong, 113-3
               Banpo-dong, Seocho-gu, Seoul, Korea

               (hereinafter called the "Company")


WITNESSETH THAT

WHEREAS, the Investor is engaged in the design and manufacture of gallium
arsenide semiconductor components and gallium arsenide-based subsystems used in
the transmission of voice, video and data over wireless communication networks;

WHEREAS, the Company is engaged in the design of personal cellular handsets used
in the CDMA and GSM telecommunication systems.

WHEREAS, the Parties to this Agreement and UBE Electronics, Ltd. ("UBE") entered
into a joint venture agreement on December 20, 2001 (the "Joint Venture
Agreement") :

WHEREAS, pursuant to and subsequent to the execution of the Joint Venture
Agreement,

      1)    the Company issued Two Hundred Thirteen Thousand Two hundred
            (213,200) new shares of Preferred Company Shares having a par value
            of Five Hundred Korean won (KRW 500) per share and the price per
            shares of Six Thousand Ninety-Eight Korean Won (KRW 6,098);

      2)    The Investor subscribed to and purchased One Hundred Six Thousand
            and Six Hundred (106,600) Preferred Company Shares for an aggregate
            consideration of Six Hundred Fifty Million Korean Won (KRW
            650,000,000) (hereinafter referred to as "Celeritek's Purchase
            Price"); and,

      3)    UBE subscribed to and purchased One Hundred Six Thousand and Six
            Hundred (106,600) Preferred Company Shares for an aggregate
            consideration of Six Hundred Fifty Million Korean Won (KRW
            650,000,000) (hereinafter referred to as "UBE's Purchase Price").

WHEREAS, the Parties are now desirous of securing further foreign invested
capital for the Company, subject to the terms and conditions set forth herein
and in the Joint Venture Agreement.

NOW, THEREFORE, in consideration of the mutual promises and covenants set forth
herein, the Parties hereby agree as follows:

ARTICLE 1.  DEFINITIONS

1.1     In this Agreement, the following expressions shall, unless the context
        otherwise requires, have the following meanings:

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        1.1.1  "Business" shall mean the business of the Company from time to
               time in accordance with the meaning specified in the Recitals
               above and in Article 3 below.

        1.1.2  "Business Day" shall mean any day on which banking institutions
               are open for normal business in Seoul, Korea.

        1.1.3  "Class A Preferred Company Shares" shall mean the First Round
               Preferred Company Shares and the Second Round Preferred Company
               Shares collectively.

        1.1.4  "Class B Preferred Company Shares" shall mean the Preferred
               Company Shares issued by the Company to the Investor and UBE on
               February 26, 2002.

        1.1.5  "Common Company Shares" shall mean any common stock issued or
               issuable by the Company.

        1.1.6  "Company Shares" shall mean all classes of stock and securities
               convertible to any class of stock, previously issued, issuable in
               accordance with the Joint Venture Agreement, this Agreement, or
               issued at any time in the future by the Company.

        1.1.7  "Execution Date" shall mean the date first above written.

        1.1.8  "First Round Investor Shares" shall mean the Preferred Company
               Shares issued to the Investors in accordance with the Joint
               Venture Agreement and, as regarding such Preferred Company
               Shares, issuable pursuant to any stock split, dividend,
               recapitalization or any other distribution except for the Class B
               Preferred Company Shares.

        1.1.9  "Foreign Capital Invested Company" shall mean a company,
               organized and registered in Korea, in which a non-Korean national
               or foreign Person has invested capital pursuant to the Foreign
               Investment Promotion Act of Korea.

        1.1.10 "Governmental Approval" shall mean all consents, approvals,
               certificates, filings, franchises, licenses, orders, permits,
               variances or similar authorizations and rights to be obtained
               from or filed with any Korean Governmental Authority required or
               necessary for any action of a Party in connection with those
               contemplated in this Agreement.

        1.1.11 "Governmental Authority" shall mean any national, regional,
               provincial, local, municipal or other political subdivision
               thereof, administrative, regulatory, judicial, legislative,
               executive, police or taxing governmental authority of any nature,
               including any ministry, agency, bureau, or entity, official, or
               court having jurisdiction.

        1.1.12 "Law" shall mean any law, rule, regulation, order, ordinance,
               code, injunction, judgment or decree, or other similar judicial
               or Governmental Authority pronouncements having compulsive legal
               effect.

        1.1.13 "Person" shall mean an individual or a corporation, association,
               partnership, limited liability company, joint venture, joint
               stock company, organization, business trust or any other entity
               or organization, including governmental entities or
               organizations.

        1.1.14 "Preferred Company Shares" shall mean any preferred class of
               voting stock or securities issued or issuable by the Company that
               have any preferential rights over Common Company Shares.

        1.1.15 "Second Round Investor Shares" shall mean the Preferred Company
               Shares issuable to the Investor in accordance with this Agreement
               and, as regarding such Preferred Company Shares, issuable
               pursuant to any stock split, dividend, recapitalization or any
               other distribution except for the Class B Preferred Company
               Shares.

1.2     Unless the context otherwise requires, words importing the singular
        shall include the plural and vice versa, the headings in this Agreement
        have been inserted for convenience of reference only and shall not be
        used in construing or interpreting this Agreement, and references to
        "Korea" shall mean the Republic of Korea.

ARTICLE 2.  PURPOSE

The purpose of this Agreement is to agree upon the terms and conditions under
which the Company shall receive further capital fund from the Investor with a
view to pursuing the Business.

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ARTICLE 3.  THE BUSINESS

The Business of the Company shall be as described and set out in Article 3 of
the Joint Venture Agreement.

ARTICLE 4.  RESPONSIBILITIES OF EACH PARTY

4.1     Prior to the Execution Date or simultaneously therewith, the Company
        shall arrange a report to be filed, on behalf of the Investor with a
        designated foreign exchange bank in Korea of the Investor's foreign
        investment in accordance with the Foreign Investment Promotion Act. The
        Investors shall provide reasonable assistance to the Company in
        connection with such filing, or any other related requirement, upon the
        Company's reasonable request.

4.2     The Company shall have the responsibility for obtaining all other
        Governmental Approvals from time to time and arising out of, or in
        connection with, the implementation of the Products, the Business and
        this Venture in the form and substance mutually agreed upon by both
        Parties.

4.3     Each Party will jointly and individually use their respective
        commercially reasonable endeavors to ensure that the Company shall
        comply with Law and continue to maintain and hold all such necessary
        license(s), approval(s) or permit(s) of any and all relevant
        Governmental Authorities.

4.4     The Company shall promptly notify the Investor in writing of any
        registrations or filings required to obtain copyright, trademark, or
        patents, in their respective names in Korea. The Company shall use
        commercially reasonable endeavors to assist the Investor in completing
        such filings or registrations or in obtaining such Government Approvals.

4.5     Each Party shall forthwith, in writing, inform the other Party upon it
        coming to its attention that an obligation pursuant to this Article 4
        has been satisfied or has been refused or rejected by a competent
        Governmental Authority.

ARTICLE 5.  CAPITAL SUBSCRIPTION

5.1     The Company shall cause to be issued and the Investor shall subscribe to
        and purchase Five Hundred Twenty-Two Thousand and Six Hundred (522,600)
        new shares of Preferred Company Shares having a par value of Five
        Hundred Korean Won (KRW 500) per share (the "Second Round Investor
        Shares") and at price per share of Four Thousand Nine Hundred and
        Seventy-Five point One Two Korean Won (KRW 4,975.12), "Original Issue
        Price" for an aggregate consideration of Two Billion Five Hundred
        Ninety-Nine Million Nine Hundred Ninety-Seven Thousand Seven Hundred and
        Twelve Korean Won (KRW 2,599,997,712) (the "Investor's Purchase Price").

        5.1.1  Simultaneously with the execution of this Agreement, the Company
               shall immediately transfer title to Five Hundred Twenty-Two
               Thousand and Six Hundred (522,600) shares of the Second Round
               Investor Shares to the Investor, and in exchange thereof, the
               Investor shall pay (by wire transfer to an account designated by
               the Company) Investor's Purchase Price within ten (10) Business
               Days from the Execution Date.

5.2     In the event of a share transfer or new issue of Company Shares
        subsequent to the subscriptions contemplated by this Agreement, the
        transferee or subscriber shall, as a condition precedent to such
        transfer or subscription, deliver a written undertaking to the Parties
        hereto, in form and substance acceptable to them, to the effect that the
        transferee or subscriber shall observe and be bound by all provisions of
        this Agreement and any agreements related hereto as if such transferee
        or a subscriber were a Party hereto and/or thereto.

5.3     The Parties shall not pledge, sell, transfer, or otherwise encumber or
        dispose of all or any Company Shares without the prior written consent
        of the other Party and unless in accordance with Section 17.1 below;
        provided, however, that the Investor may transfer its Company Shares to
        its affiliates or subsidiaries or any other third party which controls
        the Investor, or is under common control with the Investor, without the
        requirement to obtain such consent of the Company hereto.

ARTICLE 6.  RIGHTS OF THE INVESTOR

6.1     The Second Round Investor Shares shall have full voting rights pursuant
        to this Agreement and the Company's articles of incorporation, and shall
        be evidenced by share certificates in non-bearer form delivered to the
        Investor by the Company.
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6.2     Dividends. The Investor shall be entitled to receive dividends on the
        Second Round Investor Shares, out of any assets legally available
        therefore, prior and in preference to any declaration or payment of any
        dividend (payable other than in Common Company Shares or other
        securities and rights convertible into or entitling the holder thereof
        to receive, directly or indirectly, additional shares of the Common
        Company Shares) on the Common Company Shares or any other Company
        Preferred Shares, but together with and in pari passu with the holders
        of the First Round Investor Shares and Class B Preferred Company Shares,
        on a pro rata basis, at the rate of Five Hundred Korean Won (KRW 500 per
        share per annum (as adjusted to take into account any stock splits,
        stock dividends, recapitalizations or the like) or, if greater (as
        determined on a per annum basis and on an as converted basis), an amount
        equal to that paid on any other outstanding Company Shares, payable
        when, as, and if declared by the Board. Such dividends shall be
        cumulative.

6.3     Liquidation Preference.

        6.3.1  In the event of any liquidation, dissolution or winding up of the
               Company, either voluntary or involuntary, the holders of the
               Second Round Investor Shares shall each be entitled to receive,
               prior and in preference to any distribution of any of the assets
               of the Company to the holders of Common Company Shares or other
               Preferred Company Shares by reason of their ownership thereof, an
               amount per share equal to the sum of Four Thousand Nine Hundred
               Seventy-Five point One Two Korean Won (KRW 4,975.12) for each
               outstanding Second Round Investor Share, plus declared but unpaid
               dividends on such share (subject to adjustment of such fixed
               Korean Won amount for any stock splits, stock dividends,
               combinations, recapitalizations or the like), but together with
               and in pari passu with the holders of the First Round Investor
               Shares as provided in Article 6.3.1 of the Joint Venture
               Agreement. If upon the occurrence of such event, the assets and
               funds thus distributed to the holders of the Class A Preferred
               Company Shares shall be insufficient to permit the payment to
               such holders of the full aforesaid preferential amounts, then the
               entire assets and funds of the Company legally available for
               distribution shall be distributed ratably among the holders of
               the Class A Preferred Company Shares as follows (For purposes of
               this Article 6, a merger, acquisition or sale of substantially
               all of the assets of the Company shall be considered
               liquidation):

               6.3.1.1.  Any declared, but unpaid dividend shall be paid to each
                         holders of the Class A Preferred Company Shares on a
                         pro rata basis until each holder of such Preferred A
                         Company Shares has received an aggregate of Five
                         Hundred Korean Won (KRW500) per one Class A Preferred
                         Company Share. If there are remaining assets available
                         in the Company for further distribution after
                         distribution of the dividend in accordance with this
                         Section 6.3.1.1. (the "Available Fund"), they are
                         distributed in accordance with Section 6.3.1.2.

               6.3.1.2.  1) the distribution in respect of a First Round
                         Investor Share shall be equal to the sum of Celeritek's
                         Purchase Price and UBE's Purchase Price divided by the
                         sum of Celeritek' Purchase Price, UBE's Purchase Price
                         and the Investor's Purchase Price, the result of such
                         division multiplied by the amount of the Available Fund
                         and the result of such multiplication divided by the
                         number of the First Round Investor Shares.

                         2) the distribution in respect of a Second Round
                         Investor Shares shall be equal to the Investor's
                         Purchase Price divided by the sum of Celeritek's
                         Purchase Price, UBE' Purchase Price and the Investor's
                         Purchase Price, the result of such division multiplied
                         by the amount of the Available Fund and the result of
                         such multiplication divided by the number of the Second
                         Round Investor Shares.

        6.3.2  Upon the completion of the distribution required by Section 6.3.1
               above, the remaining assets of the Company available for
               distribution to its shareholders shall be distributed among the
               all of the holders of Preferred Company Shares and Common Company
               Shares, pro rata, based on the number of shares of Common Company
               Shares held by each shareholders (assuming full conversion of all
               such Preferred Company Shares to Common Company Shares) (as
               adjusted for any stock splits, stock dividends, recapitalizations
               or the like).

6.4     The Second Round Investor Shares shall not be redeemable.

6.5     Conversion. The Investor shall have the following conversion rights (the
        "Conversion Rights"):

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        6.5.1  Right to Convert. Each Second Round Investor Share shall be
               convertible, at the option of the respective holding Investor, at
               any time after the date of issuance of such share, into such
               number of fully paid and nonassessable Common Company Shares as
               is determined by dividing the Original Issue Price by the
               conversion price applicable to such share, as determined in good
               faith by the Board, in effect on the date the certificate is
               surrendered for conversion; provided, however, that such
               conversion price shall never be greater than the Original Issue
               Price. The initial conversion price per share for a Second Round
               Investor Share shall be the Original Issue Price. Conversion
               price shall be subject to adjustment which shall be effected upon
               the Board's approval if and to the extent necessary to make a
               dilution in economic value of the Second Round Investor Shares
               which may result from stock split, stock dividend.

        6.5.2  Automatic Conversion. The Second Round Investor Shares shall
               automatically be converted into Common Company Shares immediately
               upon the earlier of (i) the Company's sale of its Common Company
               Shares in a firm commitment underwritten public offering pursuant
               to a registration statement or equivalent thereof filed in
               accordance with Korean Law or (ii) the date specified by written
               consent or agreement of the holders of a majority of the then
               outstanding Class A Preferred Company Shares.

        6.5.3  Mechanics of Conversion. Before the Investor is entitled to
               convert any Second Round Investor Shares into Common Company
               Shares, the Investor shall surrender its share certificates, duly
               endorsed to the Company, and shall give written notice to the
               Company of the election. The Company shall, as soon as
               practicable thereafter, issue and deliver a certificate or
               certificates for the number of Common Company Shares to which
               such investor is entitled.

        6.5.4  Recapitalizations. If at any time or from time to time there
               shall be a recapitalization of the Common Company Shares, the
               Investor along with other holders of Preferred Company Shares
               shall thereafter be entitled to receive upon conversion of
               Preferred Company Shares the number of shares or other securities
               or property of the Company to which a holder of Common Company
               Shares deliverable upon conversion would have been entitled on
               such recapitalization.

        6.5.5  No Fractional Shares. No fractional shares shall be issued upon
               the conversion of any Second Round Investor Share. In lieu of any
               fractional shares to which the Investor would otherwise be
               entitled, the Company shall pay cash equal to such fraction
               multiplied by the then applicable conversion price.

        6.5.6  Reservation of Stock Issuable Upon Conversion. The Company shall
               at all times reserve and keep available out of its authorized but
               unissued Common Company Shares, solely for the purpose of
               effecting the conversion of the Class A Preferred Company Shares
               and Class B Preferred Company Shares, such number of its Common
               Company Shares as shall from time to time be sufficient to effect
               the conversion of all outstanding Second Round Investor Shares.

6.6     Right of First Refusal. The Investor shall have the following rights of
        first refusal:

        6.6.1  Subject to applicable Law and the Company's articles of
               incorporation, the Investor shall have rights of first refusal
               with respect to any new issuance of Company Shares in the same
               ratio as their respective shareholding ratios at the time of such
               new issuance. In the event that the Company wishes to undertake a
               new issuance of Company Shares, the Company shall first give each
               Investor prior written notice of its intention that describes the
               type of new Company Shares and the price, terms and conditions
               upon which the Company proposes to issue the same. The Investor
               shall have fifteen (15) Business Days from the day of receiving
               such notice to provide written notice back to the Company of its
               intent to purchase up to its pro rata share of such new Company
               Shares.

        6.6.2  In the event the Investor does not exercise such Investor's
               rights to purchase such new Company Shares, the Company shall
               have one hundred twenty (120) days to issue or sell such new
               Company Shares at a price and terms and conditions that are no
               more favorable than those specified in the Company's notice to
               the Investor. After the expiration of such 120-day period, the
               Company shall not thereafter issue or sell such remaining new
               Company shares without first offering such new Company Shares
               again to the Investor in accordance with this Section 6.6.

6.7     No Impairment.The Company will not through an reorganization,
        recapitalization, transfer of assets, consolidation, merger,
        dissolution, issue or sale of securities or any other voluntary action,
        avoid or seek to avoid the observance or performance of

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        any of the terms to be observed or performed hereunder by the Company
        but will at all times in good faith assist in the carrying out of all
        the provisions of this Article 6 and in the taking of such action as may
        be necessary or appropriate in order to protect the conversion rights of
        the Investor against impairment.

ARTICLE 7.   REPRESENTATIONS AND WARRANTIES

7.1     Each Party warrants and represents to the other party that (i) it is
        duly organized and in good standing; (ii) it has all necessary corporate
        power and authority to enter into this Agreement; (iii) it has duly
        authorized this Agreement by all corporate action necessary for such
        authorization; (iv) the intended this Agreement does not violate any
        charter document of such Party or judicial order binding on such Party;
        (v) this Agreement constitutes a valid and legally binding obligation of
        each Party; and (vi) it has no outstanding commitments or obligations
        which would impede its ability and right to enter into this Agreement
        and/or fulfill its obligation hereunder except those which have been
        disclosed in writing to the other Parties at the time of execution of
        this Agreement.

7.2     As of the date of this Agreement, the Company has and will have
        exclusive right, power and authority to issue and transfer the Second
        Round Investor Shares to the Investor in accordance with the terms of
        this Agreement.

7.3     The Second Round Investor Shares to which the Investor will subscribe
        hereunder shall be free and clear of all charges, liens, encumbrances,
        equities or other adverse or third Person rights, options, claims or
        interests, and with all rights, benefits, and entitlements as of the
        Execution Date, including the right to all dividends paid, declared or
        made with respect thereof. No Company Shares have been authorized or
        issued, and the Company has not become obligated to authorize or issue
        (including by reclassification or otherwise), any other equity security
        (including without limitation any Preferred Company Shares or other
        preferred security) having any preference or priority over, or ranking
        senior to, the Second Round Investor Shares with respect to any rights
        set forth in this Agreement, including but not limited to rights to
        dividends or other distributions and rights upon liquidation,
        dissolution or winding-up.

7.4     As of the Execution Date, the paid in capital of the Company is in the
        amount of One Billion Seven Hundred and Twenty Four Million Three
        Hundred Thousand Korean Won (KRW 1,724,300,000), and the Company has
        issued a total of Three Million Seven Hundred and Fifty Six Thousand Two
        Hundred (3,756,200) Common Company Shares with a par value of Five
        Hundred Korean Won (KRW 500) per share, and the Company has issued a
        total of Six Hundred and Ninety Two Thousand Four Hundred (692,400)
        Preferred Company Shares with a par value of Five Hundred Korean Won
        (KRW 500) per share.

7.5     There is no order, injunction or decree outstanding and there is no
        litigation, proceeding or governmental investigation pending or, to the
        best of the Company's knowledge, threatened against or relating to the
        Company, its property, businesses or assets which has, or if determined
        against the Company could have, a material adverse effect on the
        Company, the Company Shares, this Agreement, or the Investor's title and
        right to the Second Round Investor Shares.

ARTICLE 8.  CONFIDENTIALITY

Each Party and such Parties' respective employees, directors, consultants,
affiliates and subsidiaries shall ensure that any and all proprietary
information, trade secrets and all other confidential information regarding the
business, assets, customers, processes, and methods of any other Party that it
may learn in the course of negotiations for, or carrying out of, this Agreement
is treated by it in strict confidence and shall not use for any purpose other
than for this Agreement or the Venture or disclose such information, unless such
information (i) is required to be disclosed by Law or judicial order, (ii) is
required to be disclosed to give effect to this Agreement, (iii) is in good
faith independently acquired or developed, or (iv) becomes publicly known or
available other than through the fault of the Party seeking to use or disclose
such information.

ARTICLE 9.  TERM

This Agreement shall continue in effect so long as any Investor holds any
Company Shares unless earlier terminated pursuant to Article 10 below.

ARTICLE 10.  TERMINATION

This Agreement may be terminated upon mutual written consent of the Parties or
immediately upon notice in writing of the occurrence of one or more of the
following events:

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10.1    by the Investor, if in good faith and exercising reasonable judgment the
        board of directors of the Investor determines that (i) the
        responsibilities, policies and objectives of this Agreement, as well as
        any related agreements, have not been undertaken by the Company in form
        and substance reasonably acceptable to the Investor within ten (10)
        Business Days of the Execution Date, (ii) at any time the Company is no
        longer engaged in the Business, or (iii) within thirty (30) days of the
        Execution Date the Company has failed to obtain all of the Governmental
        Approvals required of the Venture;

10.2    by either Party, if the other Party has breached any of its obligations
        under this Agreement, and if either Party not in breach hereof has
        provided notification, in writing, to the breaching Party of its
        obligation to remedy such breach, and the breaching Party fails to
        remedy such breach to the reasonable satisfaction of either Party within
        thirty (30) Business Days from the date it received such written notice;

10.3    by either Party, if the other Party shall be or becomes incapable for a
        period of sixty (60) Business Days of performing any of its obligations
        under this Agreement subject to the terms of Article 14;

10.4    by either Party, if (i) the other Party enters into dissolution,
        liquidation, bankruptcy, reorganization or compulsory composition; (ii)
        creditors of the other Party file for the other Party's dissolution,
        liquidation, bankruptcy, reorganization or compulsory composition; (iii)
        creditors of the other Party have taken over the Company's management;
        (iv) relevant financial institutions have suspended the other Party's
        clearing house privileges; or (v) any material or significant part of
        the other Party's undertaking, property or assets is expropriated or
        confiscated by action of any government;

10.5    by the Investor, if Jay (Jongweon) Hong is no longer an employee of the
        Company for any reason within three (3) years after the Execution Date
        of the Joint Venture Agreement.

ARTICLE 11.  CONSEQUENCES OF TERMINATION

11.1    Termination of this Agreement shall be without prejudice to the accrued
        rights and liabilities of the Parties at the date of termination, unless
        waived in writing by the mutual agreement of the Parties.

11.2    Termination of this Agreement shall be accompanied by a notice of intent
        to terminate this Agreement, in writing with stated reasons, provided to
        the other Party hereto.

11.3    If this Agreement is terminated for any of the reasons set forth in
        Article 10, the Party providing notice of termination (the "Terminating
        Party") shall, at its option, have the following rights, in addition to
        any other rights to which it is entitled:

        11.3.1 If an Investor is the Terminating Party, to require the Company
               to purchase, pro rata in accordance with its ratio of
               shareholdings in the Company, all of Investor's Company Shares at
               fair market value;

        11.3.2 If the Company is the Terminating Party, to require the breaching
               Investor to sell all of the breaching Investor's Company shares
               at fair market price to the Company or a person to be designated
               by the Company

        11.3.3 The Investor may cause the Company to remove investor's name or
               names and/or its trademarks or other distinctive designations
               from the name of and from use by the Company. If a Party opts to
               request removal pursuant to this Section 11.3.3, the other
               Parties shall take all steps necessary to remove the name,
               trademark or trade name of or any reference to the party so
               opting, including the Korean language or Korea equivalent of
               such, as appropriate.

11.4    Upon termination of this Agreement for any reason, any and all
        information (whether confidential or not), data or documentation in any
        form whatsoever provided to the Company by the Investor regarding any of
        Investor's technical know-how, patents or other intellectual property
        rights, and any and all reproductions or copies thereof, shall be
        immediately returned to the Investor.

11.5    Upon termination of this Agreement for any reason, any and all
        information (whether confidential or not), data or documentation in any
        form whatsoever provided to the Investor by Company regarding any of
        Company's technical know-how, patents or other intellectual property
        rights, and any and all reproductions or copies thereof, shall be
        immediately returned to the Company.

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11.6    In the event the Parties are unable to agree within a period of thirty
        (30) Business Days upon the fair market value of any Company Shares to
        be transferred, the fair market value shall be determined by an
        independent public accountant to be chosen mutually by the Parties. The
        determination by such accountant shall be final, conclusive, and binding
        on both Parties.

11.7    Upon termination of this Agreement for any reason other than those set
        forth in Article 10 above, the Parties shall have an immediate amicable
        discussion with regard to the disposition of Company Shares owned by the
        Investor and/or the disposition of the assets and liabilities (including
        any severance obligations) of the Company. If the Parties fail to reach
        an agreement regarding disposition, the dispute shall be settled in
        accordance with Article 16 below.

11.8    In the event of termination by any Party in accordance with any
        provision of this Agreement, no Party shall be liable to the other,
        because of such termination, for compensation, reimbursement, or damages
        on account of the loss of prospective profits or anticipated sales or on
        account of expenditures, investments, or commitments in connection with
        the business or goodwill of the Parties. Termination shall not, however,
        relieve either Party of obligations incurred prior to the termination or
        obligations under subcontracts, invoices, supply agreements, original
        equipment manufacturing agreements or other similar arrangements entered
        into separately by and between the Company and the Investor (including
        such agreements entered into pursuant to Section 4.7 of the Joint
        Venture Agreement.

ARTICLE 12.  INDEMNIFICATION

Each Party agrees to indemnify, defend and hold the other Parties harmless
against any and all liabilities, losses, costs, damages, and/or expenses, which
either of them may sustain arising out of or related to a breach by such Party
of any provision of this Agreement. The Party wishing to assert its rights (the
"Indemnitee Party") set forth in this Article 12 shall notify the other Party or
Parties, as the case may be (the "Indemnitor Party") of any legal claim or legal
proceeding with respect to which such Party is asserting such right. Upon the
written request of the Indemnitee Party, the Indemnitor Party will assume the
defense of any claim, demand or action against such Indemnitee Party, and upon
request by the Indemnitee Party, will allow the Indemnitee Party to participate
in and control fully the defense thereof. Such participation will be at the
expense of the Indemnitee Party. Settlement by the Indemnitee Party, without the
Indemnitor Party's prior written consent shall release the Indemnitor Party from
the indemnity as to the claim, demand or action so settled.

ARTICLE 13.  NON WAIVER, OTHER REMEDIES

13.1    Failure of a Party to insist upon the strict and punctual performance of
        any provision hereof shall not constitute waiver of or estoppel against
        asserting the right to require such performance, nor should a waiver or
        estoppel in one case constitute a waiver or estoppel with respect to a
        later breach whether of similar nature or otherwise.

13.2    Nothing in this Agreement shall prevent a Party from enforcing its
        rights by such remedies as may be available in lieu of termination.

ARTICLE 14.  FORCE MAJEURE

14.1    The failure or delay of a Party hereto to perform any obligation under
        this Agreement solely by reason of acts of God, acts of government
        (except as otherwise enumerated herein), riots, wars, strikes, lockouts,
        accidents in transportation or other causes beyond its control shall not
        be deemed to be a breach of this Agreement; provided, however, that the
        Party so prevented from complying herewith shall continue to take all
        actions within its power to comply as fully as possible herewith.

14.2    Except where the nature of the event shall prevent it from doing so, the
        Party suffering such force majeure shall notify the other Party in
        writing within five (5) Business Days after the occurrence of such force
        majeure and shall in every instance, to the extent it is capable of
        doing so, use its best efforts to remove or remedy such cause with all
        reasonable dispatch.

ARTICLE 15.  DISCLAIMER OF AGENCY

15.1    Nothing in this Agreement shall constitute or be deemed to constitute
        the relationship of principal, representative or agent as between the
        Parties.

15.2    Nothing in this Agreement or in any document referred to in it shall
        constitute a partnership between the Parties, nor shall the execution,
        completion and implementation of this Agreement confer on any Party (i)
        the power to bind or impose any obligations

<PAGE>

        on the other Party in regards to any third Persons, or (ii) the power,
        ability, or right to pledge the credit of the other Party.

ARTICLE 16.  DISPUTE RESOLUTION

16.1    All dispute, controversies, or differences which may arise between the
        Parties out of or in relation to or in connection with this Agreement,
        or for the breach hereof, shall be finally settled by arbitration before
        three (3) arbitrators under the Rules of Arbitration of the
        International Chamber of Commerce in Korea. Each Party shall be entitled
        to nominate one arbitrator. If dispute, controversies, or differences
        arise between two of the Parties hereto, each Party shall be entitled to
        nominate one arbitrator and the arbitrators so selected by the Parties
        shall mutually agree upon the selection of the third arbitrator. The
        arbitration proceeding shall be conducted in English. The results of
        such arbitration shall be conclusive and binding upon the parties, and
        shall be enforceable in any court having jurisdiction over the party
        against whom the award was rendered.

16.2    Each Party hereto agrees to pay and discharge all reasonable costs,
        attorney fees and expenses that are incurred by another Party in
        enforcing the terms of this Agreement, provided that such other Party
        shall prevail in such proceedings.

16.3    The validity, performance, construction, and effect of this Agreement
        shall be interpreted in accordance with and governed by the substantive
        Laws of the Republic of Korea, without regard to conflicts of laws
        provisions.

ARTICLE 17.  MISCELLANEOUS

17.1    Assignability. This Agreement and each and every covenant, term and
        condition hereof shall be binding upon and effective to the benefit of
        the Parties hereto and their respective successors and assignees, but
        neither this Agreement nor any rights or obligations hereunder shall be
        assignable directly or indirectly by any Party hereto without the prior
        written consent of the other Party; provided, however, that the Investor
        may transfer its Company Shares without such consent of the Company in
        accordance with Section 5.3 above. Any Person who becomes a holder of
        Second Round Investor Shares pursuant to this Agreement shall, as a
        condition precedent to receiving such shares and exercising rights as a
        shareholder of the Company, execute and become a Party to this Agreement
        and shall be bound by all of its terms and conditions.

17.2    Expenses. Each Party shall bear its own attorney fees and other expenses
        incurred in the preparation and execution of this Agreement, and any
        other related agreement provided hereunder, and the performance of the
        Parties' respective obligations hereunder, and the Parties shall hold
        each other harmless for any such charges.

17.3    Modification. No amendment, change, addition or modification of the
        terms set forth in this Agreement shall be effective or binding upon
        either of the Parties unless reduced to writing and executed by the
        respective duly authorized representatives of each Party.

17.4    Severability. In the event any term or provision of this Agreement shall
        for any reason be invalid, illegal or unenforceable in any respect, such
        invalidity, illegality or unenforceability shall not affect any other
        term or provision of this Agreement and this Agreement shall be
        interpreted and construed as if such term or provision, to the extent
        unenforceable, had never been contained in this Agreement.

17.5   Notice.

        17.5.1 Any notice required or permitted to be given hereunder shall be
               in writing and may be given by personal service, registered
               airmail, or by facsimile if confirmed on the same day in writing
               by registered airmail, with postage fully prepaid to the
               following addresses:

               If to The Investor:
                                    3236 Scott Blvd.,
                                    Santa Clara, California
                                    United States of America

               If to the Company:
                                    NewGen Telecom Corporation
                                    2nd Floor, Duk Myung Bldg A-Dong,
                                    113-3, Banpo-Dong, Seocho-Ku,
                                    Seoul, Korea
<PAGE>

        17.5.2 Except as otherwise specified herein, all notices, demands, and
               other communications shall be deemed to have been duly given on
               the date of receipt if delivered personally or by facsimile or
               fifteen (15) Business Days after the date of mailing if sent by
               registered airmail.

        17.5.3 All notices, demands or other communications hereunder and any
               other documents required to be delivered hereunder shall be in
               the English language or accompanied by a certified translation
               thereof into the English language.

17.6    Counterparts. This Agreement is written in the English language and may
        be executed in multiple counterparts, each of which shall be deemed an
        original but all of which together shall constitute one document.

17.7    Language. The English language text of this Agreement shall prevail over
        any translation thereof for purposes of interpretation and resolving
        ambiguities.

17.8    Applicability of the Joint Venture Agreement. Notwithstanding Section
        17.8 and any other provisions in this Agreement, nothing herein shall be
        deemed to limit the validity or applicability of the Joint Venture
        Agreement, and every provision thereof shall be applicable to the
        parties to this Agreement, unless expressly provided otherwise in this
        Agreement, and to the extent that there arises no conflict between this
        Agreement and the Joint Venture Agreement. In case of conflict, this
        Agreement shall prevail over the Joint Venture Agreement and be taken as
        correct.

17.9    Headings. The headings contained in this Agreement are for the
        convenience of the reader only and shall not in any way affect the
        meaning or interpretation of this Agreement.

IN WITNESS WHEREOF, the authorized representatives of the Parties hereto have
caused this Agreement to be executed as of the date first above written.

Celeritek, Inc.



By      /s/ KWON HOE KIM
   -------------------------------

Name:   Kwon Hoe Kim

Title:  Legal Representative


NewGen Telecom Co.



By      /s/ JONGWEON HONG
   ------------------------------

Name:    Jongweon Hong

Title:  Chief Executive Officer